A few years ago, when my daughter was in Kindergarten, she was reading a book to me on the couch. She was laying at one end, and I was laying at the other. Just having a nice quiet time while everyone else was out of the room. Suddenly I noticed that while she was reading, she would start looking to her left furtively. Her reading would drop off for a second or two while she quickly turned her head, looked annoyed, and then turned back to continue reading. This happened several times but I didnt say anything. I thought perhaps an errant hair was sticking out past her head and she could see something but couldnt figure it out. So I just watched her. But then she changed from quickly turning her head, to slowly turning her head while she was peeking as far out of the corner of her eye as she could. It was starting to get bizarre, but I still just watched her.
There was nothing else beside or behind her aside from the wall and the front door of the house. She kept reading and darting her eyes to the left, like she was trying to catch sight of something sneaking up on her. Then she started to get really annoyed and would huff and puff and Grrrrrrrr when she turned and apparently saw nothing.
I finally said "What are you doing??" and she put the book down on her lap and said "That white light is really starting to annoy me". I said "What white light??" and she said "A bright white light. It's beside or behind me but when I turn my head to see it, it's gone, and then it comes back". She was annoyed and frustrated by something that I could not see and I had full view of her and everything beside and behind her the entire time.
I had a very sudden vision or impression of my grandmother, my dad's mom, standing a little behind her and watching over her shoulder to see her reading. I dont know why that happened, and the 'impression' was gone as fast as it popped into my brain. I call it an impression because it's not like I 'saw' or envisioned my grandmother standing there, it's more like I felt it. It's so hard to explain. I don't recall anything like that happening before. So I said, really loud inside my head, 'Grandma if that's you, stand back a bit, cos my daughter can see you and it's distracting her!". My daughter picked up her book and started reading again, and I think she looked over her shoulder one more time, but that was it. She didn't look there again.
What was it? Heck if I know lol, but it was weird! Hasnt happened before or since then either.