Yeah, how I see it, I see it like Erza's mother from Fairy Tail. She'll tell him that her magic prevented her belly from growing while she was pregnant, but he won't believe her, and then it'll all start with this nonsense. Maybe it'll be when she gives birth and the child looks like him that he'll realize, "Oh no, I was wrong." Or when he sees either the scar or her using magic, he'll understand that everything she said was true, and he'll start crying because he didn't trust his wife. He didn't believe her from the beginning.