diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index 3322ecd..f916645 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -14,6 +14,9 @@ Change Log
 Unreleased
 ~~~~~~~~~~
 
+[4.2.1]- 2023-04-26
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+* Support ``get_child_blocks`` along with ``get_child_descriptors``.
 * Switch from ``edx-sphinx-theme`` to ``sphinx-book-theme`` since the former is
   deprecated
 
diff --git a/completion/__init__.py b/completion/__init__.py
index d0efb25..00d812e 100644
--- a/completion/__init__.py
+++ b/completion/__init__.py
@@ -2,6 +2,6 @@
 Completion App
 """
 
-__version__ = '4.2.0'
+__version__ = '4.2.1'
 
 default_app_config = 'completion.apps.CompletionAppConfig'  # pylint: disable=invalid-name
diff --git a/completion/services.py b/completion/services.py
index 13e051a..14174e2 100644
--- a/completion/services.py
+++ b/completion/services.py
@@ -93,7 +93,9 @@ def get_completable_children(self, node):
         user_children = []
         mode = XBlockCompletionMode.get_mode(node)
         if mode == XBlockCompletionMode.AGGREGATOR:
+            # TODO: `get_child_descriptors` will be renamed to `get_child_blocks` in the Redwood release.
             node_children = ((hasattr(node, 'get_child_descriptors') and node.get_child_descriptors())
+                             or (hasattr(node, 'get_child_blocks') and node.get_child_blocks())
                              or (hasattr(node, 'get_children') and node.get_children()))
             for child in node_children:
                 user_children.extend(self.get_completable_children(child))