diff --git a/CHANGELOG.md b/CHANGELOG.md
index 932f1da8..429b815f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,7 +8,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [1.4.1] - 2026-05-02
 ### Changed:
-- Tree Search: Modify type hint to include returning None
+- Tree Helper: Tree diff modify type hint to include returning None.
+- Misc: Mypy type checks to remove ignoring warn_no_return.
+
+## [1.4.1] - 2026-05-02
+### Changed:
+- Tree Search: Modify type hint to include returning None.
 - Misc: Clean up and remove redundant lines.
 
 ## [1.4.0] - 2026-03-24
diff --git a/bigtree/node/basenode.py b/bigtree/node/basenode.py
index 84a7eda0..37bde59c 100644
--- a/bigtree/node/basenode.py
+++ b/bigtree/node/basenode.py
@@ -458,6 +458,7 @@ def left_sibling(self: T) -> T | None:
             child_idx = children.index(self)
             if child_idx:
                 return self.parent.children[child_idx - 1]
+        return None
 
     @property
     def right_sibling(self: T) -> T | None:
@@ -471,6 +472,7 @@ def right_sibling(self: T) -> T | None:
             child_idx = children.index(self)
             if child_idx + 1 < len(children):
                 return self.parent.children[child_idx + 1]
+        return None
 
     @property
     def node_path(self: T) -> Iterable[T]:
diff --git a/bigtree/tree/helper.py b/bigtree/tree/helper.py
index 314ed4b8..d216663e 100644
--- a/bigtree/tree/helper.py
+++ b/bigtree/tree/helper.py
@@ -441,7 +441,7 @@ def get_tree_diff(
     aggregate: bool = False,
     attr_list: Iterable[str] | None = None,
     fallback_sep: str = "/",
-) -> node.Node:
+) -> node.Node | None:
     """Get difference of `tree` to `other_tree`, changes are relative to `tree`.
 
     Compares the difference in tree structure (default), but can also compare tree attributes using `attr_list`.
@@ -692,3 +692,4 @@ def get_tree_diff(
                 _node = search.find_full_path(tree_diff, path)
                 _node.name += " (~)"
         return tree_diff
+    return None
diff --git a/bigtree/tree/search.py b/bigtree/tree/search.py
index e85b2fce..b93e5199 100644
--- a/bigtree/tree/search.py
+++ b/bigtree/tree/search.py
@@ -117,8 +117,7 @@ def find(tree: T, condition: Callable[[T], bool], max_depth: int = 0) -> T | Non
         Search result
     """
     result = findall(tree, condition, max_depth, max_count=1)
-    if result:
-        return result[0]
+    return result[0] if result else None
 
 
 def find_name(tree: NodeT, name: str, max_depth: int = 0) -> NodeT | None:
@@ -206,9 +205,7 @@ def find_relative_path(tree: NodeT, path_name: str) -> NodeT | None:
         Search result
     """
     result = find_relative_paths(tree, path_name, max_count=1)
-
-    if result:
-        return result[0]
+    return result[0] if result else None
 
 
 def find_relative_paths(
@@ -532,8 +529,7 @@ def find_child(
         Search result
     """
     result = find_children(tree, condition, max_count=1)
-    if result:
-        return result[0]
+    return result[0] if result else None
 
 
 def find_child_by_name(tree: NodeT | DAGNodeT, name: str) -> NodeT | DAGNodeT | None:
diff --git a/pyproject.toml b/pyproject.toml
index 992a7481..d05c1d7f 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -169,7 +169,6 @@ profile = "black"
 ignore_missing_imports = true
 strict = true
 strict_optional = false
-warn_no_return = false
 disallow_untyped_calls = false
 
 [tool.ruff]