diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index a1e69ecfeb..eb49be24e7 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -293,6 +293,13 @@ jobs:
       uses: actions/checkout@v2
       with:
         submodules: recursive
+
+    # the default python 3.8 doesn't cut it, and causes mongo-orchestration
+    # to fail in mongodb-labs/drivers-evergreen-tools.
+    - uses: actions/setup-python@v5
+      with:
+        python-version: '3.13'
+
     - id: start-mongodb
       name: start mongodb
       uses: mongodb-labs/drivers-evergreen-tools@master
diff --git a/lib/mongoid/interceptable.rb b/lib/mongoid/interceptable.rb
index 34fb684940..fbd0e5246e 100644
--- a/lib/mongoid/interceptable.rb
+++ b/lib/mongoid/interceptable.rb
@@ -141,9 +141,13 @@ def run_callbacks(kind, with_children: true, &block)
     # @api private
     def _mongoid_run_child_callbacks(kind, children: nil, &block)
       if Mongoid::Config.around_callbacks_for_embeds
-        _mongoid_run_child_callbacks_with_around(kind, children: children, &block)
+        _mongoid_run_child_callbacks_with_around(kind,
+                                                 children: children,
+                                                 &block)
       else
-        _mongoid_run_child_callbacks_without_around(kind, children: children, &block)
+        _mongoid_run_child_callbacks_without_around(kind,
+                                                    children: children,
+                                                    &block)
       end
     end
 
@@ -218,9 +222,6 @@ def _mongoid_run_child_before_callbacks(kind, children: [], callback_list: [])
         return false if env.halted
         env.value = !env.halted
         callback_list << [next_sequence, env]
-        if (grandchildren = child.send(:cascadable_children, kind))
-          _mongoid_run_child_before_callbacks(kind, children: grandchildren, callback_list: callback_list)
-        end
       end
       callback_list
     end
diff --git a/spec/mongoid/interceptable_spec.rb b/spec/mongoid/interceptable_spec.rb
index 1c75b0c94c..ab2ed5574f 100644
--- a/spec/mongoid/interceptable_spec.rb
+++ b/spec/mongoid/interceptable_spec.rb
@@ -388,6 +388,84 @@ class TestClass
         end
       end
     end
+
+    context 'with embedded grandchildren' do
+      IS = InterceptableSpec
+
+      context 'when creating' do
+        let(:registry) { IS::CallbackRegistry.new(only: %i[ before_save ]) }
+
+        let(:expected_calls) do
+          [
+            # the parent
+            [ IS::CbParent, :before_save ],
+
+            # the immediate child of the parent
+            [ IS::CbCascadedNode, :before_save ],
+
+            # the grandchild of the parent
+            [ IS::CbCascadedNode, :before_save ],
+          ]
+        end
+
+        let!(:parent) do
+          parent = IS::CbParent.new(registry)
+          child = IS::CbCascadedNode.new(registry)
+          grandchild = IS::CbCascadedNode.new(registry)
+
+          child.cb_cascaded_nodes = [ grandchild ]
+          parent.cb_cascaded_nodes = [ child ]
+
+          parent.tap(&:save)
+        end
+
+        it 'should cascade callbacks to grandchildren' do
+          expect(registry.calls).to be == expected_calls
+        end
+      end
+
+      context 'when updating' do
+        let(:registry) { IS::CallbackRegistry.new(only: %i[ before_update ]) }
+
+        let(:expected_calls) do
+          [
+            # the parent
+            [ IS::CbParent, :before_update ],
+
+            # the immediate child of the parent
+            [ IS::CbCascadedNode, :before_update ],
+
+            # the grandchild of the parent
+            [ IS::CbCascadedNode, :before_update ],
+          ]
+        end
+
+        let!(:parent) do
+          parent = IS::CbParent.new(nil)
+          child = IS::CbCascadedNode.new(nil)
+          grandchild = IS::CbCascadedNode.new(nil)
+
+          child.cb_cascaded_nodes = [ grandchild ]
+          parent.cb_cascaded_nodes = [ child ]
+
+          parent.save
+
+          parent.callback_registry = registry
+          child.callback_registry = registry
+          grandchild.callback_registry = registry
+
+          parent.name = 'updated'
+          child.name = 'updated'
+          grandchild.name = 'updated'
+
+          parent.tap(&:save)
+        end
+
+        it 'should cascade callbacks to grandchildren' do
+          expect(registry.calls).to be == expected_calls
+        end
+      end
+    end
   end
 
   describe ".before_destroy" do
diff --git a/spec/mongoid/interceptable_spec_models.rb b/spec/mongoid/interceptable_spec_models.rb
index 71e7680899..7b72afee8b 100644
--- a/spec/mongoid/interceptable_spec_models.rb
+++ b/spec/mongoid/interceptable_spec_models.rb
@@ -1,10 +1,12 @@
 module InterceptableSpec
   class CallbackRegistry
-    def initialize
+    def initialize(only: [])
       @calls = []
+      @only = only
     end
 
     def record_call(cls, cb)
+      return unless @only.empty? || @only.any? { |pat| pat == cb }
       @calls << [cls, cb]
     end
 
@@ -15,6 +17,8 @@ module CallbackTracking
     extend ActiveSupport::Concern
 
     included do
+      field :name, type: String
+
       %i(
         validation save create update
       ).each do |what|
@@ -34,196 +38,128 @@ module CallbackTracking
         end
       end
     end
-  end
 
-  class CbHasOneParent
-    include Mongoid::Document
-
-    has_one :child, autosave: true, class_name: "CbHasOneChild", inverse_of: :parent
+    attr_accessor :callback_registry
 
-    def initialize(callback_registry)
+    def initialize(callback_registry, *args, **kwargs)
       @callback_registry = callback_registry
-      super()
+      super(*args, **kwargs)
     end
+  end
 
-    attr_accessor :callback_registry
-
+  module RootInsertable
     def insert_as_root
       @callback_registry&.record_call(self.class, :insert_into_database)
       super
     end
+  end
 
+  class CbHasOneParent
+    include Mongoid::Document
     include CallbackTracking
+    include RootInsertable
+
+    has_one :child, autosave: true, class_name: "CbHasOneChild", inverse_of: :parent
   end
 
   class CbHasOneChild
     include Mongoid::Document
+    include CallbackTracking
 
     belongs_to :parent, class_name: "CbHasOneParent", inverse_of: :child
-
-    def initialize(callback_registry)
-      @callback_registry = callback_registry
-      super()
-    end
-
-    attr_accessor :callback_registry
-
-    include CallbackTracking
   end
 
   class CbHasManyParent
     include Mongoid::Document
+    include CallbackTracking
+    include RootInsertable
 
     has_many :children, autosave: true, class_name: "CbHasManyChild", inverse_of: :parent
-
-    def initialize(callback_registry)
-      @callback_registry = callback_registry
-      super()
-    end
-
-    attr_accessor :callback_registry
-
-    def insert_as_root
-      @callback_registry&.record_call(self.class, :insert_into_database)
-      super
-    end
-
-    include CallbackTracking
   end
 
   class CbHasManyChild
     include Mongoid::Document
+    include CallbackTracking
 
     belongs_to :parent, class_name: "CbHasManyParent", inverse_of: :children
-
-    def initialize(callback_registry)
-      @callback_registry = callback_registry
-      super()
-    end
-
-    attr_accessor :callback_registry
-
-    include CallbackTracking
   end
 
   class CbEmbedsOneParent
     include Mongoid::Document
+    include CallbackTracking
+    include RootInsertable
 
     field :name
 
     embeds_one :child, cascade_callbacks: true, class_name: "CbEmbedsOneChild", inverse_of: :parent
-
-    def initialize(callback_registry)
-      @callback_registry = callback_registry
-      super()
-    end
-
-    attr_accessor :callback_registry
-
-    def insert_as_root
-      @callback_registry&.record_call(self.class, :insert_into_database)
-      super
-    end
-
-    include CallbackTracking
   end
 
   class CbEmbedsOneChild
     include Mongoid::Document
+    include CallbackTracking
 
     field :age
 
     embedded_in :parent, class_name: "CbEmbedsOneParent", inverse_of: :child
-
-    def initialize(callback_registry)
-      @callback_registry = callback_registry
-      super()
-    end
-
-    attr_accessor :callback_registry
-
-    include CallbackTracking
   end
 
   class CbEmbedsManyParent
     include Mongoid::Document
+    include CallbackTracking
+    include RootInsertable
 
     embeds_many :children, cascade_callbacks: true, class_name: "CbEmbedsManyChild", inverse_of: :parent
-
-    def initialize(callback_registry)
-      @callback_registry = callback_registry
-      super()
-    end
-
-    attr_accessor :callback_registry
-
-    def insert_as_root
-      @callback_registry&.record_call(self.class, :insert_into_database)
-      super
-    end
-
-    include CallbackTracking
   end
 
   class CbEmbedsManyChild
     include Mongoid::Document
+    include CallbackTracking
 
     embedded_in :parent, class_name: "CbEmbedsManyParent", inverse_of: :children
-
-    def initialize(callback_registry)
-      @callback_registry = callback_registry
-      super()
-    end
-
-    attr_accessor :callback_registry
-
-    include CallbackTracking
   end
 
   class CbParent
     include Mongoid::Document
-
-    def initialize(callback_registry)
-      @callback_registry = callback_registry
-      super()
-    end
-
-    attr_accessor :callback_registry
+    include CallbackTracking
 
     embeds_many :cb_children
     embeds_many :cb_cascaded_children, cascade_callbacks: true
-
-    include CallbackTracking
+    embeds_many :cb_cascaded_nodes, cascade_callbacks: true, as: :parent
   end
 
   class CbChild
     include Mongoid::Document
+    include CallbackTracking
 
     embedded_in :cb_parent
-
-    def initialize(callback_registry, options)
-      @callback_registry = callback_registry
-      super(options)
-    end
-
-    attr_accessor :callback_registry
-
-    include CallbackTracking
   end
 
   class CbCascadedChild
     include Mongoid::Document
+    include CallbackTracking
 
     embedded_in :cb_parent
 
-    def initialize(callback_registry, options)
-      @callback_registry = callback_registry
-      super(options)
-    end
+    before_save :test_mongoid_state
 
-    attr_accessor :callback_registry
+    private
+
+    # Helps test that cascading child callbacks have access to the Mongoid
+    # state objects; if the implementation uses fiber-local (instead of truly
+    # thread-local) variables, the related tests will fail because the
+    # cascading child callbacks use fibers to linearize the recursion.
+    def test_mongoid_state
+      Mongoid::Threaded.stack('interceptable').push(self)
+    end
+  end
 
+  class CbCascadedNode
+    include Mongoid::Document
     include CallbackTracking
+
+    embedded_in :parent, polymorphic: true
+
+    embeds_many :cb_cascaded_nodes, cascade_callbacks: true, as: :parent
   end
 end