About me: I'm single, live alone and no kids.

My dream:
My brother and his wife are visiting and staying at my parents house, in my old bedroom. After visiting with them in the room, I feel uneasy. I try and explain this to them and tell them I think it's a bad idea to stay in the room. They don't listen and I head out. Soon as I exit the door, it slams shut. I begin to feel the prescence of an evil spirit. I begin yelling at the door (can't recall exactally what...but it's along these lines) "you're not welcome here...you can't hurt them". I'm yelling this at the top of my lungs and also fearful of being attacked and for my brother and his wife. I feel myself get exhausted and after a few minutes I'm still yelling but no words are coming out.

Next thing I know, the door and walls vanish. But only to me. I can see into the bedroom, and my brother and his wife are acting normal. Someone behind me (who I can't see and don't recognize the voice) say to me "You did it".

I go into the next room over, because I feel like the spirit moved to that room. In that room was a baby girl with black hair, that belonged to my brother (in real life, they have a baby son with brown hair). I noticed the window was wide open and no screen. As I close the window (which is in a corner, connected to the window of the previous room) I hear my sister in law yell at me ( in a demonic sounding voice, but still english) "don't shut that window!" and something else but I can't recall what. I leave the window half open and explain I was afraid the baby would crawl out and fall. My sister in law just stares at me with hateful eyes.

At this point I woke up. I've never had dreams about spirits (good or evil). 

I've always had a bad habit of holding in my emotions, which could be a reason for the screaming...but it's weird because I'm yelling at an evil spirit. Trying to think of what's going on in my life, I don't feel fearful of anything, or that love/attention was snatched away from me. Though I do want love/attention from someone outside of family (i.e a significant other), which I don't have.

And my sister in law does prefer to do things her way. If often leads to arguments with my brother and father.

My biggest question is how an evil spirit fits into the dream. The reason I'm calling it evil is because when it was around I felt uncomfortable and not safe.