My DS1 had an imaginary friend that was a little bee. DS1 told me once that his little bee left him a yellow highlighter pen and he thought it was amazing. I have no idea where it came from and to this day, neither does DS1 (who is now almost 17).

One day when DS1 was about 6 he told me that his little bee had to fly away to be with his family and he was never seen again.