What is wrong with my sis? She is very controlling regarding the way I put myself.?

She acts like she is my mum, probing into things that doesnt concern her, like whether I make my bed, or when i bought a new headphone. She will always tell my mum if she finds out I am trying things i never did before, like dying my hair, going for piercing. The bad thing is, she will try her best to convince my mum that what I am doing is wrong. She also has a weird habit of staying up late just to see what time i sleep, so that she could report to my mum. When I stayed up later than usual (i usually sleep at 12am), she will wake my mum up to tell her to tell me to go to bed (my mum has to work in the morning!!) Some things she do just does not make sense. She would move things i put on my bed (books, earphones) onto my table. That really PISS me off. I really hate her. WHY CAN'T SHE MIND HER OWN BUSINESS?