Is it right my mum lets my youngest brother 15 come back home in 1 in the morning from a party?

This isn’t the first time! He’s only just turned 15 and no one really knows the friends he hangs out with and all he does now is go out with his friends whether he’s actually doing something or finding something to do and my mum has no concern with him being out past 12 even with the minimum communication they have. I’m always the one trying to keep updated as to where my brother is and my mum is just calm about things. It’s really pissing me off! This couldn’t ride as a female when I was 15 so I don’t understand why it’s okay for him? What, cause he’s a boy? Kmt I’m so pissed. Looking at the time now, it’s 01:04 in the morning!
Is it right my mum lets my youngest brother 15 come back home in 1 in the morning from a party?
Post Opinion