Gremlin?

I wasn't going to post anything about this, but at this point I'm just curious.

Probably 5 months ago my brother continuously complained about this thing that he fondly named a "Gremlin". He said it looked like a short black creature that would mess with his things and crawl around in his bed at night. I didn't believe him at all. I just figured he was dreaming or that he was making it up to scare me.

Time passed, and my parents had gone away for a couple days, leaving it just me, him, and our dog at home. We talked a lot about the "Gremlin", and managed to kind of spook ourselves. Over the next couple days his door would open and close, his light would turn on when no one was in the room, and we'd hear noises. Once I even spotted something going around the corner near his bedroom. Needless to say we were frightened.

When our parents came home everything seemed to go back to normal, minus my brother complaining about odd nightmares he would have starring this weird creature. At least until one night anyways.

It was probably 3am, and I was the only one awake since I tend to stay up late. I had heard light, quick footsteps walking around near my father's room, and then heard a door open and close multiple times. I'd just figured it had been my dog being loud, or maybe someone had woken up.

The next day my mother went in to the garage to get her purse, before quickly coming back inside. Her purse was missing, and it looked like someone had poured its contents all over her vehicle. I didn't tell them about the noises I had heard the previous night, and was still in denial.

A couple months passed without incident, until my brother nonchalantly declared that the "Gremlin" was gone. Apparently it had migrated from his room to mine because I started having experiences. I'd see small shadows darting around my room, things would be moved from where I originally put them, and I'd see my blanket rise right next to me in bed. Once when I rolled it even felt like I rolled on something solid, but nothing was there.

My mom said it might be an animal spirit, but I don't think so. It just doesn't act like an animal. The thing honestly freaks me out, and I'd like to know what you guys think it could be. I'd like it gone, mostly because it's annoying me by moving all my things and preventing me from sleeping.