What's wrong with Cinderalla

This story for me is very hard to comprehend because I grew up with a brother and the only thing we both wanted to do was play sports outside and come home dirty to the point where my mom would make us change in the garage. I've never had to face the whole princess phase because it never came up in my life, but in the past few years, when my cousin got married and had kids, I came to realize what the princess phase is. My cousin had a girl about 4 years ago and right when she was born, she instantly became a princess. Then, two months later, my other cousin had a baby girl who was instantly a princess. As they went from infant to small child, they fell in love with princess and barbies and it's only because that's what they were attracted to. Now, one of the 4 years olds doesn't take crap from her older brother, who is 6. Now, I don't think that because she likes princesses that she's automatically a prissy girl. Little girls might like something like princesses or barbies, but that shouldn't decide their futures. I have come to realize that I don't have much say in this topic, but from my observation with my cousin's little girl, that is something she likes and that's it.