I HATE this society!

Shantelle • ♉️
Today my little brothers school is having a dance, where all the kids from Kindergarten-3rd grade will dress up as fairytale characters. Of course there's lots of costumes for superheroes but that's not the theme; however there are so many Disney princesses to choose from. 
My little brother has 2 big sisters, me included, who loved Disney princesses. We owned lots of movies and we had heaps of Barbie dolls. When he was born me and my sister were still very in to all of that, so obviously he'd want to play too: so now, this almost 5 year old little boy loves Disney princesses and wanted to dress up as Rapunzel. My mom didn't know what to do, of course she wanted to make her son happy, she has no problem with her son loving princesses but we both feel he'll be bullied or laughed at. 
This pisses me off so much, why do people have to make a big thing about this? Now I'm not saying my brother is gay or transgender because boys can like things that are stereotypically girls things, but why can we let people of all ages enjoy the things they like? Why do we have to fear that our little brothers, or sons will no longer have friends because their parents don't want them around them. Kids are cruel, I know that from experience. I just wished things were different.
Sorry for this rant, I'm just so upset