Cringe. I have never done the terrible things I did in this dream. It's not for the sqeamish.

I was a home care provider. I encountered the old man I was to care for, his teenage daughter, and an Asian woman who was some sort of intermediary. We entered an elevator, going down. All the time I was speaking to the old man and the daughter in a patronizing tone of voice, as if they were infants, because for some reason I thought they were retarded. When we exited the elevator, I finally asked the daughter, "Are you retarded?" She said, "No, but sometimes people assume we are."
The old man was in a wheelchair, and was sleeping. He could just as easily have been comatose, or dead- I never saw him move or breathe. I took his wheelchair and brought him home- to my mom's house, where I no longer live. Then I forgot about him. It was terrible. I didn't do didley-sqat for this poor old man. I just left him in his wheelchair for the night.
In the morning, it occured to me that I should take the old man to the bathroom. He was soaked in urine. So I wheeled him into the bathroom. Then I forgot about him again. I went to another bathroom to take a shower. But I was so spaced out, I couldn't focus on that task either. I got my shampoo and stuff but then I moved on to something else.
For whatever reason, I was angry at my little sister (she's 10). I really wanted to hurt her. So did my brother (14). So we gave her his murderous toy, ala "Chucky". First it was a panda bear. We brought it into my sister's room, we told her we were giving her a present. She was so happy to get it, but she said "What do I do with it?" Now it was a huge baby's head, made up of a bunch of little metallic units and mounted on a base. It was bald, with a pigtail coming out of the top of it's head. The ponytail was made up of the same units. And the baby was wearing sunglasses. I took the sunglasses off, trying to incite this baby, cause I knew it would go on a rampage if I could get it angry. Then it had a body, and it wasn't connected to the base. It took its ponytail in its hand and started swinging it at my sister, like a lasso. I told my sister, "Oh, don't touch the sunglasses". Then I ran, closing her door behind me.
And then I remembered the old man. It was a real Oh, Shit! moment. I went into the bathroom, and there he was, still in his wheelchair. He was soaked, beyond soaked, in urine- apparently he had drowned in it. And his head, which previously had been bent forward into his chest, had got so wet and heavy that it broke off at the nape. The skin there was broken, and the wound was bright red against his yellow skin. He was dead. It was so disgusting, I was terrified.
Then I went downstairs, and the doll I had gotten my sister was on th rampage. It was using its pigtail as a projectile weapon. My sister was crying to my mother. There was chaos, and it was my fault.