My 6 year old DS believes in Santa and the tooth fairy and likes stories like The Faraway tree and The Wishing chair and last week he discovered a secret door in his bedroom-(the kind you can buy and put on the skirting board) and I like to encourage it all -One of my friends thinks he's getting too old for it and maybe I shouldn't encourage him with things like the door-a few of the boys at school seem much older and are quite serious boys -should I stop?