diff --git a/gtk/gtktextchild.c b/gtk/gtktextchild.c
index a7d2fa1860..2571ad605c 100644
--- a/gtk/gtktextchild.c
+++ b/gtk/gtktextchild.c
@@ -414,6 +414,7 @@ gtk_text_child_anchor_new (void)
 
 /**
  * gtk_text_child_anchor_new_with_replacement:
+ * @character: a replacement character
  *
  * Creates a new `GtkTextChildAnchor` with the given replacement character.
  *