A friend of mine (she is 34) was a big fan of an actor called Keith O'Sullivan. It was only very recently that we discovered that she was in fact talking about Kiefer Sutherland.
A childhood belief about films

others believed things like this
- I recently very disturbed to learn that Al Jolson was in fact Caucasian.Anon
- My friend's sister believed the lyrics to Gazza's "Fog on the Tyne" were "Fog on the dinasaurs mine all mine"— Suzanne
- Until recently, my friend believed that Richard Starkey was the fifth Beatle.— Spook
- I used to believe that all parents were called "Inge and Dirk", just like mine— eva
- A friend of mine seemed to think that 100 pence was worth £6.— Richard Davies
- A friend of mine thought that some olives grew with red edible pits (pimentos).— HA