DS asked about Santa right before he turned four (he has a December bday). At that time I didn't want to tell him the truth right before Christmas, and he seemed so young. But this year right after Christmas he was still talking about it, and I decided that for a kid like himself, it would be better for him not to keep lying to him even under the guise of, "just a fun tradition". Knowing him, I know he would not take it well, and it would call into question everything else I told him - including religious beliefs - and I didn't want those to get tangled in his mind with fairy tales, myths, etc. I still feel really odd about having to break it to him so young...he didn't even make it to his first "Tooth Fairy" visit. On that night, he told me to go dress up in my fairy costume and get my wand so that I could trick him. BTW, he still wants to believe and pretend in it - just for fun.