spiteful bed wetting

so as this moment I speak I was woken up by pee dripping down on me I recently switched around the mattress (it for a bunk bed ) thinking that my 11 year old sister had stop bed wetting but now I'm convinced that its spite full it not a you wake up in the morning and notice you peed its peed and eyes wide open laying there trying to pretend like nothing happened .

I am so angry right now I had to get up and switch back around the mattress and took a bath , now the rooms smells of pee