Depp's Wonka isn't at all sure how to talk to kids. He (Wonka, not Depp) is very nervous, he freezes up, he reads from cue cards, he switches gears abruptly. It was an interesting acting choice on Depp's part, but it's heavy-handed and not always believable. Wonka is so afraid of his father that he's incapable of uttering the word "parents" (he doesn't have any trouble with the word "father", though).