diff --git a/manimlib/animation/transform_matching_parts.py b/manimlib/animation/transform_matching_parts.py
index 51e69e6c..c37c16c3 100644
--- a/manimlib/animation/transform_matching_parts.py
+++ b/manimlib/animation/transform_matching_parts.py
@@ -83,19 +83,22 @@ class TransformMatchingParts(AnimationGroup):
         new_source_pieces = source.family_members_with_points()
         new_target_pieces = target.family_members_with_points()
         if len(new_source_pieces) == 0 or len(new_target_pieces) == 0:
-            # Don't animate null sorces
+            # Don't animate null sorces or null targets
             return
         source_is_new = all(char in self.source_pieces for char in new_source_pieces)
         target_is_new = all(char in self.target_pieces for char in new_target_pieces)
-        if source_is_new and target_is_new:
-            transform_type = self.mismatch_animation 
-            if source.has_same_shape_as(target):
-                transform_type = self.match_animation
-            self.anims.append(transform_type(source, target, **self.anim_config))
-            for char in new_source_pieces:
-                self.source_pieces.remove(char)
-            for char in new_target_pieces:
-                self.target_pieces.remove(char)
+        if not source_is_new or not target_is_new:
+            return
+
+        transform_type = self.mismatch_animation 
+        if source.has_same_shape_as(target):
+            transform_type = self.match_animation
+
+        self.anims.append(transform_type(source, target, **self.anim_config))
+        for char in new_source_pieces:
+            self.source_pieces.remove(char)
+        for char in new_target_pieces:
+            self.target_pieces.remove(char)
 
     def find_pairs_with_matching_shapes(
         self,
@@ -136,8 +139,8 @@ class TransformMatchingStrings(TransformMatchingParts):
                 for substr in [
                     *source.get_specified_substrings(),
                     *target.get_specified_substrings(),
-                    *source.get_string(),  # TODO, have this return symbols, not characters
-                    *target.get_string(),
+                    *source.get_symbol_substrings(),
+                    *target.get_symbol_substrings(),
                 ]
             ]
         ]