DS6 started reading fluently just before his 5th birthday. He'd been asking me since he was 3 to teach him, but I (mistakenly as it were) believed that he should wait for Kindergarten. He just one day picked up one of the leveled easy readers and started reading it. Within a month he was reading Magic Treehouse.
At the time I thought it was completely spontaneous, but having spent some time reading about other people's experiences with early readers, I'm sure that he was showing signs much earlier. By 18mo he had every kids book we owned memorized and could memorize books from the library after 1 or 2 readings and then remember them if he saw them later. He was probably 2 when he started with some sight words, I just didn't think that counted for anything because they were just memorized, right? When he was 3 I thought that him asking me to teach him to read was cute, but he didn't really understand what he wanted. At 3.5 he started writing sentences and became really interested in the spellings of words and how the letters came together. But, he was asking me how to spell them, so it didn't mean anything.
I use the "just before his 5th birthday" marker as my answer for when he started reading. It's the one that I'm most comfortable with and since I can name books he was reading, it makes it easier to explain to other people.
