So a bit of background, my mother works nightshift, and I babysit my little brother for her overnight. I'm 18. Our neighbour who is in her mid to late 80's was actually really nice, we've lived here for 4 years, and she's brung us Christmas gifts, etc. She's always been lovely. But today, she came banging on the door like the police. And when we opened the door, she pushed me aside and demanded my mother who was home for like 1 hour from her night shift. She started telling her "you've no idea what he does to me" (pointing at me). "banging all night, running up and down stairs all night", "Purposely banging on the wall", and acting like I'm actually doing all this to purposely annoy her. (Just to say, I don't make lots of noise. I might occasionally listen to the radio through the Amazon Echo but 90% of the time I use earphones on my PC at night). I was completely speechless, and she started getting really close to me and pointing in my face, and actually was scaring me if I'm honest as she seemed very unhinged. My mum is actually a care home nurse for people with dementia, ironically, so she was good and kept a clear head but I was absolutely flabbergasted at this woman saying this. She also said that I was shouting at my cat, and shouting at my little brother, which is really upsetting to me because my cat is my pride and joy, I'd never shout or hurt him or anything. And my brother, who was as surprised as me if I'm honest. It's really upsetting hear her say this. Then she actually said if It happens again she'll call the police. I don't know what to do, even if she does call the police what do I say? Does this sound like she has dementia? It got to a point that she wouldn't actually leave the house, so we did start walking towards the door and she eventually left but I'm scared she'll wake up in the middle of the night, having thought she's heard something, and calls the police. She must be hearing things or dreaming about things. Thanks.