And as for North West's birthday hairstyle — a stick-straight ponytail that the Internet flipped out about — that's NBD to the selfie-loving star, either, really. "She wanted to try straight hair so I said she could try it for her birthday party and then if she liked it, she could do it in New York for her birthday. It's very limited to just that," she said. "I think everyone thought it was this crazy pressed thing — I mean, I just used a flat iron and everyone was saying she was wearing extensions and I was like, 'No, she has curly hair, so that's what the length of her hair is when it's straightened.'"