Does he like to watch TV? My son (easy child, not difficult child) loves to watch videos. His favorites used to be learning ones by First Impressions. We started with the Left Brain and Right Brain ones and the alphabet is part of the Left brain video I think. Anyway, he learned the alphabet before he was two (before he even talked really). He's going to be three next week and he can spell tons of words and write the entire alphabet. I would love to think it's because I taught him so well, but that's not it at all, he just liked to watch that video. He's on to other shows now, but I only let him watch shows with some educational value and I limit the time each day.
I agree with the others though, it's not because of anything you're doing wrong. My difficult child is now 16 and I remember reading to him all the time when he was little, but I don't remember spending time teaching him this stuff, I'm sure he learned it in school, and your son will too!!!
