I don’t know if this would be considered an “Imaginary friend”, but this happened around I was 4/5/6 (don’t exactly remember)
It was a couple of months after my grandfather died because of lung cancer(he used to smoke), and we were living with my grandmother at the time. One day I was on the couch and my grandmother was talking about her wedding with my Grandfather, I ended up saying “I was at your wedding…” They explain to me I wasn’t and my grandmother asked me questions about it and I answered every one correctly about the marriage.
I think this was a week before or after, but on that day I was talking to myself (I usually talk a lot to myself, and I still do.), and my mom walked in and asked who I was talking to. My mother told me I responded with “I’m talking to Pap-pap”
A couple of months passed after these events, and they start re-asking me and telling me if I remember talking to my Grandfather, I forgot everything…
When I was 8, I remember getting ready for school and my grandma was still asleep. This is forever in my mind, I see a white figure the same shape he is and I saw him walk into the bathroom.
That was the last time I saw or talked to him.