My mother lets my brother take my things and i'm just supposed to let him

My brother is 4. he doesn't know what he's doing. my mother on the other hand, is well above 4, and knows exactly what she's doing. I'm just supposed to let him take my paint, my brushes, my keychains, my bags, my perfumes, my lip balms, EVERYTHING. and i'm just supposed to let him. she then yells at ME when i try to take my things back. he has already lost one of my fav keychains, he's ruined my black paint by filling it up with water, thrown my oil pastels and colour pencils, ruined my eyeliner, and so many more things.

the frustrating thing is she tells me to stop 'being a drama queen' and to 'grow up' and to 'consider his age' when i get upset but he's ruining my things! what do i even do other than be upset? just say "oh ok you can take my things its ok" like wtf is the logic.

and one time i lost it and began to cry, and i said i was upset that everyone else my age was allowed to enjoy their summer and i have to either take care of him when my mum is out or deal with this behaviour, to the point i've barely been able to enjoy or relax, because when i try to paint or crochet or watch something, he comes to bother me. she then told me to look at those who don't have as much as me, and the only reason i'm upset is because i'm looking at people more privileged than me.

even now, my brother told ME to leave MY room so i don't stop him from taking my stuff, and all she can ever say is "stop causing problems, why do you always want to fight him?"

i love both of them, and i don't blame my brother because he's little. i just wish my mother would control him and stop him from ruining my things, especially when i'm at school and unable to stop him. there were many times where i'd come home to find my things all over the house, broken, ruined, and my mum just goes "oh yeah he took that, but i didn't see until later so i just moved it"

i just wanted to get it off my chest. feels much better after putting my frustration in words