diff --git a/sunspot/lib/sunspot/dsl/field_query.rb b/sunspot/lib/sunspot/dsl/field_query.rb
index b66eeacac..e61aada49 100644
--- a/sunspot/lib/sunspot/dsl/field_query.rb
+++ b/sunspot/lib/sunspot/dsl/field_query.rb
@@ -52,6 +52,12 @@ def order_by_geodist(field_name, lat, lon, direction = nil)
         )
       end
 
+      def order_by_child_document(field_name, direction = nil, block_join:)
+        @query.add_sort(
+          Sunspot::Query::Sort::ChildDocumentSort.new(field_name, block_join, direction)
+        )
+      end
+
       #
       # DEPRECATED Use <code>order_by(:random)</code>
       #
diff --git a/sunspot/lib/sunspot/field_factory.rb b/sunspot/lib/sunspot/field_factory.rb
index a01c84324..c4f4e941f 100644
--- a/sunspot/lib/sunspot/field_factory.rb
+++ b/sunspot/lib/sunspot/field_factory.rb
@@ -1,5 +1,5 @@
 module Sunspot
-  # 
+  #
   # The FieldFactory module contains classes for generating fields. FieldFactory
   # implementation classes should implement a #build method, although the arity
   # of the method depends on the type of factory. They also must implement a
@@ -41,7 +41,7 @@ def extract_value(model, options = {})
       end
     end
 
-    # 
+    #
     # A StaticFieldFactory generates normal static fields. Each factory instance
     # contains an eager-initialized field instance, which is returned by the
     # #build method.
@@ -60,14 +60,14 @@ def initialize(name, type, options = {}, &block)
           end
       end
 
-      # 
+      #
       # Return the field instance built by this factory
       #
       def build
         @field
       end
 
-      # 
+      #
       # Extract the encapsulated field's data from the given model and add it
       # into the Solr document for indexing.
       #
@@ -90,7 +90,7 @@ def populate_document(document, model, options = {}) #:nodoc:
         end
       end
 
-      # 
+      #
       # A unique signature identifying this field by name and type.
       #
       def signature
@@ -107,7 +107,7 @@ def initialize(name, type, options = {}, &block)
         @field = JoinField.new(self.name, type, options)
       end
 
-      # 
+      #
       # Return the field instance built by this factory
       #
       def build
@@ -122,7 +122,7 @@ def signature
       end
     end
 
-    # 
+    #
     # DynamicFieldFactories create dynamic field instances based on dynamic
     # configuration.
     #
@@ -141,13 +141,13 @@ def initialize(name, type, options = {}, &block)
       def build(dynamic_name)
         AttributeField.new([@name, dynamic_name].join(separator), @type, @options.dup)
       end
-      # 
+      #
       # This alias allows a DynamicFieldFactory to be used in place of a Setup
       # or CompositeSetup instance by query components.
       #
       alias_method :field, :build
 
-      # 
+      #
       # Generate dynamic fields based on hash returned by data accessor and
       # add the field data to the document.
       #
@@ -167,7 +167,7 @@ def populate_document(document, model, options = {})
         end
       end
 
-      # 
+      #
       # Unique signature identifying this dynamic field based on name and type
       #
       def signature
@@ -193,7 +193,7 @@ def extract_value(model, options = {})
         # TODO(ar3s3ru): how to handle incorrect field values?
         values  = @extractor.value_for(model)
         adapter = options[:adapter]
-        unless values.is_a? Array
+        unless values.is_a?(Array) || rails_association?(values)
           raise 'Child documents field must be an Array of indexable documents'
         end
         if adapter.nil? || !adapter.respond_to?(:call)
@@ -206,6 +206,13 @@ def extract_value(model, options = {})
       def signature
         [field, ::RSolr::Document::CHILD_DOCUMENT_KEY]
       end
+
+      private
+
+      def rails_association?(values)
+        return false unless defined?(ActiveRecord::Associations::CollectionProxy)
+        values.is_a?(ActiveRecord::Associations::CollectionProxy)
+      end
     end
   end
 end
diff --git a/sunspot/lib/sunspot/indexer.rb b/sunspot/lib/sunspot/indexer.rb
index 8cb2419dc..70702bded 100644
--- a/sunspot/lib/sunspot/indexer.rb
+++ b/sunspot/lib/sunspot/indexer.rb
@@ -1,7 +1,7 @@
 require 'sunspot/batcher'
 
 module Sunspot
-  # 
+  #
   # This class presents a service for adding, updating, and removing data
   # from the Solr index. An Indexer instance is associated with a particular
   # setup, and thus is capable of indexing instances of a certain class (and its
@@ -12,7 +12,7 @@ def initialize(connection)
       @connection = connection
     end
 
-    # 
+    #
     # Construct a representation of the model for indexing and send it to the
     # connection for indexing
     #
diff --git a/sunspot/lib/sunspot/query/block_join.rb b/sunspot/lib/sunspot/query/block_join.rb
index 4a661903b..fe54c4eed 100644
--- a/sunspot/lib/sunspot/query/block_join.rb
+++ b/sunspot/lib/sunspot/query/block_join.rb
@@ -152,7 +152,11 @@ def all_parents_filter
           # to select which parents are used in the query.
           fq = filter_query.to_params[:fq]
           raise 'allParents filter must be non-empty!' if fq.nil?
-          fq[0] # Type filter used by Sunspot
+          Util.escape(fq[0]) # Type filter used by Sunspot
+        end
+
+        def facet_type_filter
+          filter_query.to_params[:fq][0]
         end
 
         def secondary_filter
@@ -176,9 +180,18 @@ def to_params
       class ParentWhich < Abstract
         alias some_children_filter secondary_filter
 
-        def all_parents_filter
+        def all_parents_parts
           # Use top-level scope (on parent type) as allParents filter.
-          scope.to_params[:fq].flatten.join(' AND ')
+          parts = scope.to_params[:fq].flatten
+          parts.map { |v| Util.escape(v) }
+        end
+
+        def all_parents_filter(*args)
+          all_parents_parts(*args).join(' AND ')
+        end
+
+        def facet_type_filter
+          scope.to_params[:fq].flatten[0]
         end
 
         def secondary_filter
@@ -190,10 +203,21 @@ def secondary_filter
           q
         end
 
+        def field_list_string
+          parts = []
+          parts << '[child'
+          parts << 'parentFilter="' + all_parents_parts[0] + '"'
+          parts << 'childFilter="' + secondary_filter.map { |f| Util.escape(f) }.join(' AND ') + '"]'
+          parts.join(' ')
+        end
+
         def to_params
-          { q: render_query_string('parent', 'which') }
+          {
+            q: render_query_string('parent', 'which'),
+            fl: [:id] + [field_list_string]
+          }
         end
       end
     end
   end
-end
\ No newline at end of file
+end
diff --git a/sunspot/lib/sunspot/query/block_join_json_facet.rb b/sunspot/lib/sunspot/query/block_join_json_facet.rb
index eeaf0b80c..2adb9d532 100644
--- a/sunspot/lib/sunspot/query/block_join_json_facet.rb
+++ b/sunspot/lib/sunspot/query/block_join_json_facet.rb
@@ -62,7 +62,7 @@ def field_name_with_local_params
               type: 'terms',
               field: @field.indexed_name,
               domain: {
-                @operator => @query.all_parents_filter,
+                @operator => @query.facet_type_filter,
                 FILTER_OP => generate_filter
               }
             }.merge!(init_params)
@@ -78,4 +78,4 @@ def generate_filter
       end
     end
   end
-end
\ No newline at end of file
+end
diff --git a/sunspot/lib/sunspot/query/sort.rb b/sunspot/lib/sunspot/query/sort.rb
index dcc1bb7aa..31ff99198 100644
--- a/sunspot/lib/sunspot/query/sort.rb
+++ b/sunspot/lib/sunspot/query/sort.rb
@@ -1,11 +1,11 @@
 module Sunspot
   module Query
-    # 
+    #
     # The classes in this module implement query components that build sort
     # parameters for Solr. As well as regular sort on fields, there are several
     # "special" sorts that allow ordering for metrics calculated during the
     # search.
-    # 
+    #
     module Sort #:nodoc: all
       DIRECTIONS = {
         :asc => 'asc',
@@ -15,7 +15,7 @@ module Sort #:nodoc: all
       }
 
       class <<self
-        # 
+        #
         # Certain field names are "special", referring to specific non-field
         # sorts, which are generally by other metrics associated with hits.
         #
@@ -30,7 +30,7 @@ def special(name)
         end
       end
 
-      # 
+      #
       # Base class for sorts. All subclasses should implement the #to_param
       # method, which is a string that is then concatenated with other sort
       # strings by the SortComposite to form the sort parameter.
@@ -42,11 +42,11 @@ def initialize(direction)
 
         private
 
-        # 
+        #
         # Translate fairly forgiving direction argument into solr direction
         #
         def direction_for_solr
-          DIRECTIONS[@direction] || 
+          DIRECTIONS[@direction] ||
             raise(
               ArgumentError,
               "Unknown sort direction #{@direction}. Acceptable input is: #{DIRECTIONS.keys.map { |input| input.inspect } * ', '}"
@@ -54,7 +54,7 @@ def direction_for_solr
         end
       end
 
-      # 
+      #
       # A FieldSort is the usual kind of sort, by the value of a particular
       # field, ascending or descending
       #
@@ -71,7 +71,7 @@ def to_param
         end
       end
 
-      # 
+      #
       # A RandomSort uses Solr's random field functionality to sort results
       # (usually) randomly.
       #
@@ -79,7 +79,7 @@ class RandomSort < Abstract
         def initialize(options_or_direction=nil)
           if options_or_direction.is_a?(Hash)
             @seed, @direction = options_or_direction[:seed], options_or_direction[:direction]
-					else
+          else
             @direction = options_or_direction
           end
 
@@ -91,7 +91,7 @@ def to_param
         end
       end
 
-      # 
+      #
       # A ScoreSort sorts by keyword relevance score. This is only useful when
       # performing fulltext search.
       #
@@ -155,6 +155,21 @@ def to_s
           "#{function}(#{fields.map(&:to_s).join(",")})"
         end
       end
+
+      #
+      # A ChildDocumentSort sorts on child documents.
+      #
+      class ChildDocumentSort < Abstract
+        def initialize(field_name, block_join, direction)
+          @field_name = field_name
+          @block_join = block_join
+          @direction = (direction || :asc).to_sym
+        end
+        def to_param
+          field = Setup.for(@block_join[:type]).field(@field_name)
+          "childfield(#{field.indexed_name}) #{@direction}"
+        end
+      end
     end
   end
 end
diff --git a/sunspot/lib/sunspot/search/field_json_facet.rb b/sunspot/lib/sunspot/search/field_json_facet.rb
index 139e09a31..2dfa161c5 100644
--- a/sunspot/lib/sunspot/search/field_json_facet.rb
+++ b/sunspot/lib/sunspot/search/field_json_facet.rb
@@ -5,7 +5,8 @@ class FieldJsonFacet
       attr_reader :name
 
       def initialize(field, search, options)
-        @name, @search, @options = name, search, options
+        @search, @options = search, options
+        @name = (options[:name] || field.name)
         @field = field
       end
 
diff --git a/sunspot/lib/sunspot/search/hit.rb b/sunspot/lib/sunspot/search/hit.rb
index f7a698b27..e70e22fcf 100644
--- a/sunspot/lib/sunspot/search/hit.rb
+++ b/sunspot/lib/sunspot/search/hit.rb
@@ -1,6 +1,6 @@
 module Sunspot
   module Search
-    # 
+    #
     # Hit objects represent the raw information returned by Solr for a single
     # document. As well as the primary key and class name, hit objects give
     # access to stored field values, keyword relevance score, and keyword
@@ -9,15 +9,15 @@ module Search
     class Hit
       SPECIAL_KEYS = Set.new(%w(id type score)) #:nodoc:
 
-      # 
+      #
       # Primary key of object associated with this hit, as string.
       #
       attr_reader :primary_key
-      # 
+      #
       # Class name of object associated with this hit, as string.
       #
       attr_reader :class_name
-      # 
+      #
       # Keyword relevance score associated with this result. Nil if this hit
       # is not from a keyword search.
       #
@@ -33,8 +33,9 @@ def initialize(raw_hit, highlights, search) #:nodoc:
         @stored_values = raw_hit
         @stored_cache = {}
         @highlights = highlights
+        @child_documents = (raw_hit['_childDocuments_'] || []).map { |h| Hit.new(h, highlights, search) }
       end
-      
+
       #
       # Returns all highlights for this hit when called without parameters.
       # When a field_name is provided, returns only the highlight for this field.
@@ -55,7 +56,7 @@ def highlight(field_name)
         highlights(field_name).first
       end
 
-      # 
+      #
       # Retrieve stored field value. For any attribute field configured with
       # :stored => true, the Hit object will contain the stored value for
       # that field. The value of this field will be typecast according to the
@@ -80,7 +81,7 @@ def stored(field_name, dynamic_field_name = nil)
         @stored_cache[field_key] = stored_value(field_name, dynamic_field_name)
       end
 
-      # 
+      #
       # Retrieve the instance associated with this hit. This is lazy-loaded, but
       # the first time it is called on any hit, all the hits for the search will
       # load their instances using the adapter's #load_all method.
@@ -110,6 +111,11 @@ def to_param
         self.primary_key
       end
 
+      def children(type = nil)
+        return @child_documents if type.nil?
+        @child_documents.select { |d| d.class_name == type.name }
+      end
+
       private
 
       def setup
diff --git a/sunspot/lib/sunspot/search/hit_enumerable.rb b/sunspot/lib/sunspot/search/hit_enumerable.rb
index 6e2b58aa9..1806bfd16 100644
--- a/sunspot/lib/sunspot/search/hit_enumerable.rb
+++ b/sunspot/lib/sunspot/search/hit_enumerable.rb
@@ -18,7 +18,7 @@ def verified_hits
         hits.select { |h| h.result }
       end
 
-      # 
+      #
       # Populate the Hit objects with their instances. This is invoked the first
       # time any hit has its instance requested, and all hits are loaded as a
       # batch.
@@ -27,10 +27,13 @@ def populate_hits #:nodoc:
         id_hit_hash = Hash.new { |h, k| h[k] = {} }
         hits.each do |hit|
           id_hit_hash[hit.class_name][hit.primary_key] = hit
+          hit.children.each do |child_hit|
+            id_hit_hash[child_hit.class_name][child_hit.primary_key] = child_hit
+          end
         end
         id_hit_hash.each_pair do |class_name, hits|
           ids = hits.map { |id, hit| hit.primary_key }
-          data_accessor = data_accessor_for(Util.full_const_get(class_name))          
+          data_accessor = data_accessor_for(Util.full_const_get(class_name))
           hits_for_class = id_hit_hash[class_name]
           data_accessor.load_all(ids).each do |result|
             hit = hits_for_class.delete(Adapters::InstanceAdapter.adapt(result).id.to_s)
@@ -53,7 +56,7 @@ def each_hit_with_result
         verified_hits.each { |hit| yield hit, hit.result }
       end
 
-      # 
+      #
       # Get the data accessor that will be used to load a particular class out of
       # persistent storage. Data accessors can implement any methods that may be
       # useful for refining how data is loaded out of storage. When building a
diff --git a/sunspot/lib/sunspot/session.rb b/sunspot/lib/sunspot/session.rb
index 15f455c6e..252ddbe71 100644
--- a/sunspot/lib/sunspot/session.rb
+++ b/sunspot/lib/sunspot/session.rb
@@ -87,6 +87,7 @@ def more_like_this(object, *types, &block)
     #
     def index(*objects)
       objects.flatten!
+      verify_indexing_parents!(objects)
       @adds += objects.length
       indexer.add(objects)
     end
@@ -279,5 +280,14 @@ def setup_for_types(types)
         CompositeSetup.for(types)
       end
     end
+
+    def verify_indexing_parents!(objects)
+      # http://yonik.com/solr-nested-objects#Limitations
+      # Child and parent documents must be indexed in the same block
+      objects.each do |object|
+        next unless Setup.for(object.class).is_child
+        raise 'Child documents must be indexed with their parent'
+      end
+    end
   end
 end
diff --git a/sunspot_rails/lib/sunspot/rails/searchable.rb b/sunspot_rails/lib/sunspot/rails/searchable.rb
index f308c5212..24bfff1be 100644
--- a/sunspot_rails/lib/sunspot/rails/searchable.rb
+++ b/sunspot_rails/lib/sunspot/rails/searchable.rb
@@ -1,6 +1,6 @@
 module Sunspot #:nodoc:
   module Rails #:nodoc:
-    # 
+    #
     # This module adds Sunspot functionality to ActiveRecord models. As well as
     # providing class and instance methods, it optionally adds lifecycle hooks
     # to automatically add and remove models from the Solr index as they are
@@ -16,7 +16,7 @@ def included(base) #:nodoc:
       end
 
       module ActsAsMethods
-        # 
+        #
         # Makes a class searchable if it is not already, or adds search
         # configuration if it is. Note that the options passed in are only used
         # the first time this method is called for a particular class; so,
@@ -28,7 +28,7 @@ module ActsAsMethods
         # complete information on the functionality provided by that method.
         #
         # ==== Options (+options+)
-        # 
+        #
         # :auto_index<Boolean>::
         #   Automatically index models in Solr when they are saved.
         #   Default: true
@@ -53,9 +53,9 @@ module ActsAsMethods
         #   to ignore.
         # :include<Mixed>::
         #   Define default ActiveRecord includes, set this to allow ActiveRecord
-        #   to load required associations when indexing. See ActiveRecord's 
+        #   to load required associations when indexing. See ActiveRecord's
         #   documentation on eager-loading for examples on how to set this
-        #   Default: [] 
+        #   Default: []
         # :unless<Mixed>::
         #   Only index models in Solr if the method, proc or string evaluates
         #   to false (e.g. <code>:unless => :should_not_index?</code> or <code>
@@ -109,7 +109,7 @@ def searchable(options = {}, &block)
           end
         end
 
-        # 
+        #
         # This method is defined on all ActiveRecord::Base subclasses. It
         # is false for classes on which #searchable has not been called, and
         # true for classes on which #searchable has been called.
@@ -138,7 +138,7 @@ class <<base
             alias_method :atomic_update!, :solr_atomic_update! unless method_defined? :atomic_update!
           end
         end
-        # 
+        #
         # Search for instances of this class in Solr. The block is delegated to
         # the Sunspot.search method - see the Sunspot documentation for the full
         # API.
@@ -167,7 +167,7 @@ def solr_search(options = {}, &block)
           end
         end
 
-        # 
+        #
         # Get IDs of matching results without loading the result objects from
         # the database. This method may be useful if search is used as an
         # intermediate step in a larger find operation. The block is the same
@@ -183,14 +183,14 @@ def solr_search_ids(&block)
           end
         end
 
-        # 
+        #
         # Remove instances of this class from the Solr index.
         #
         def solr_remove_all_from_index
           Sunspot.remove_all(self)
         end
 
-        # 
+        #
         # Remove all instances of this class from the Solr index and immediately
         # commit.
         #
@@ -199,7 +199,7 @@ def solr_remove_all_from_index!
           Sunspot.remove_all!(self)
         end
 
-        # 
+        #
         # Completely rebuild the index for this class. First removes all
         # instances from the index, then loads records and indexes them.
         #
@@ -217,7 +217,7 @@ def solr_reindex(options = {})
         # records will not be indexed in batches. By default, a commit is issued
         # after each batch; passing +false+ for +batch_commit+ will disable
         # this, and only issue a commit at the end of the process. If associated
-        # objects need to indexed also, you can specify +include+ in format 
+        # objects need to indexed also, you can specify +include+ in format
         # accepted by ActiveRecord to improve your sql select performance
         #
         # ==== Options (passed as a hash)
@@ -235,18 +235,18 @@ def solr_reindex(options = {})
         #            specify something reasonable here.
         #
         # ==== Examples
-        #   
+        #
         #   # index in batches of 50, commit after each
-        #   Post.index 
+        #   Post.index
         #
         #   # index all rows at once, then commit
-        #   Post.index(:batch_size => nil) 
+        #   Post.index(:batch_size => nil)
         #
         #   # index in batches of 50, commit when all batches complete
-        #   Post.index(:batch_commit => false) 
+        #   Post.index(:batch_commit => false)
         #
         #   # include the associated +author+ object when loading to index
-        #   Post.index(:include => :author) 
+        #   Post.index(:include => :author)
         #
         def solr_index(opts={})
           options = {
@@ -315,22 +315,22 @@ def solr_atomic_update!(updates = {})
           Sunspot.atomic_update!(self, updates)
         end
 
-        # 
+        #
         # Return the IDs of records of this class that are indexed in Solr but
         # do not exist in the database. Under normal circumstances, this should
         # never happen, but this method is provided in case something goes
         # wrong. Usually you will want to rectify the situation by calling
         # #clean_index_orphans or #reindex
-        # 
+        #
         # ==== Options (passed as a hash)
         #
         # batch_size<Integer>:: Override default batch size with which to load records.
-        # 
+        #
         # ==== Returns
         #
         # Array:: Collection of IDs that exist in Solr but not in the database
         def solr_index_orphans(opts={})
-          batch_size = opts[:batch_size] || Sunspot.config.indexing.default_batch_size          
+          batch_size = opts[:batch_size] || Sunspot.config.indexing.default_batch_size
 
           solr_page = 0
           solr_ids = []
@@ -343,7 +343,7 @@ def solr_index_orphans(opts={})
           return solr_ids - self.connection.select_values("SELECT id FROM #{quoted_table_name}").collect(&:to_i)
         end
 
-        # 
+        #
         # Find IDs of records of this class that are indexed in Solr but do not
         # exist in the database, and remove them from Solr. Under normal
         # circumstances, this should not be necessary; this method is provided
@@ -352,7 +352,7 @@ def solr_index_orphans(opts={})
         # ==== Options (passed as a hash)
         #
         # batch_size<Integer>:: Override default batch size with which to load records
-        # 
+        #
         def solr_clean_index_orphans(opts={})
           solr_index_orphans(opts).each do |id|
             new do |fake_instance|
@@ -361,7 +361,7 @@ def solr_clean_index_orphans(opts={})
           end
         end
 
-        # 
+        #
         # Classes that have been defined as searchable return +true+ for this
         # method.
         #
@@ -372,7 +372,7 @@ def solr_clean_index_orphans(opts={})
         def searchable?
           true
         end
-        
+
         def solr_execute_search(options = {})
           inherited_attributes = [:include, :select, :scopes]
           options.assert_valid_keys(*inherited_attributes)
@@ -393,10 +393,10 @@ def solr_execute_search_ids(options = {})
           search = yield
           search.raw_results.map { |raw_result| raw_result.primary_key.to_i }
         end
-        
+
         protected
-        
-        # 
+
+        #
         # Does some logging for benchmarking indexing performance
         #
         def solr_benchmark(batch_size, counter,  &block)
@@ -422,7 +422,7 @@ def self.included(base) #:nodoc:
             alias_method :atomic_update!, :solr_atomic_update! unless method_defined? :atomic_update!
           end
         end
-        # 
+        #
         # Index the model in Solr. If the model is already indexed, it will be
         # updated. Using the defaults, you will usually not need to call this
         # method, as models are indexed automatically when they are created or
@@ -434,7 +434,7 @@ def solr_index
           Sunspot.index(self)
         end
 
-        # 
+        #
         # Index the model in Solr and immediately commit. See #index
         #
         def solr_index!
@@ -457,8 +457,8 @@ def solr_atomic_update(updates = {})
         def solr_atomic_update!(updates = {})
           Sunspot.atomic_update!(self.class, self.id => updates)
         end
-        
-        # 
+
+        #
         # Remove the model from the Solr index. Using the defaults, this should
         # not be necessary, as models will automatically be removed from the
         # index when they are destroyed. If you disable automatic removal
@@ -469,7 +469,7 @@ def solr_remove_from_index
           Sunspot.remove(self)
         end
 
-        # 
+        #
         # Remove the model from the Solr index and commit immediately. See
         # #remove_from_index
         #