A childhood belief about imaginary friends

I used to love the TV show "Punky Brewster" and I wanted a dog exactly like Punky's, the golden retreiver. Well, I was at the age where children start developing invisible friends and such. ...Well, my imaginary friend happened to have been a dog named "Brandon". He was exactly like the dog on Punky Brewster, except he was all white and he could talk. He went to preschool with me, slept in the same bed as me, and even ran beside us while we were driving in a car (on the freeway?). Mind you, no one knew this imaginary friend/dog existed except myself. Sooo, one day, my mother was getting ready to sit down on the couch and I started screaming. Crying hysterically, and she was like "WHAT?>!?! WHAT?!?!" and I go, "YOU'RE GONNA SIT ON BRANDON!!!!!!!!" ...she looked at the couch, looked back at me and goes, "Oh, sorry, I didn't see 'Brandon' sitting there......" and she sat down at the other end of the couch. I don't think she has thought I was very "sane" since that day...