Time to burn down the dollhouse and say your sister must have done it

Seriously call child services

two words... MOVE OUT

As a now adult sibling of someone with mental issues, I can understand more where my mother was coming from when I was "punished" for my brothers violent outbursts. While it may not make sense, it it ridiculously stressful for a parent to have a mentally troubled child. So they may punish the stronger child to feel like they still have control as parents, and also potentially for your safety. I was once banned from my house daily from 7am to 10pm for three weeks in high school because my brother was becoming increasingly aggressive towards me. Now I see my mom was doing it for my safety as well as she new I was stronger than him and could go someplace during this time. It was hard for her to do but it kept me safe and kept my brother calm. So I'm here for you OP if you need anything.

As a fellow pyromaniac, I am here to tell you that pyromania is only provoked in a few isolated cases. Most of the time, the person will do it regardless.

Calmly take your pyro sister, light your dad's bed on fire, and throw your sister into it... Then take her out of course, don't kill her, once she gets burned by a flaming bed she'll probably stop liking fire that much. Once dad comes in, say that your sister set it on fire because she didn't like the doll house... After burning that up too.

Ian's people wonder what's wrong with kids these days

is this the plot to a horror movie??

How old is she?

You need to contact a doctor or an officer or therapist or the fire department now