diff --git a/gtk/gtklistbox.c b/gtk/gtklistbox.c
index be879d45c7..85c8585dbf 100644
--- a/gtk/gtklistbox.c
+++ b/gtk/gtklistbox.c
@@ -721,7 +721,8 @@ gtk_list_box_get_row_at_index (GtkListBox *box,
  *
  * Gets the row at the @y position.
  *
- * Returns: (transfer none): the row
+ * Returns: (transfer none) (nullable): the row or %NULL
+ *   in case no row exists for the given y coordinate.
  *
  * Since: 3.10
  */