I noticed that my niece is so critical about physical appearance.

one time she had her hair done (her natural hair is fuzzy and not soft, she suffers to comb it every day) and it was nice and silky, easy to comb etc. but as soon as she finished she went to her older sister saying "my hair is so much better than you !!" (he sister's natural hair is soft and silky and brownish). Her sister never says such things to her, she never makes the little one feel conscious about her appearance which made me think it's weird.

Another time we were playing, my little niece and I, and then she said "What is this hair! (pointing to my very soft facial hair that you can barely see) do you have a beard ?" .. I was confused a bit and I thought about that extra hair on her arm that her mother removes it for her every now and then. (as if hair is not a natural process of a human body)

At other time we were all sitting together with my mother (her grandma) and she started saying "Grandma, why are you so fat !? Look how my mum is thin (which is not entirely true) and look how I am thin .. ", she said it in a teasing manner, as if she is superior to her grandma.

Is that normal ?

Note : as a family we don't behave like this. Never we try to put others down . we never make her feel bad about herself. that's why I don't know where this is coming from.