They probably were - I read the newspaper at breakfast every morning beginning at age 5 until I went off to college. For some people, learning to read is a process. For others, it's more of an instant epiphany. I've seen two year olds who were doing a pretty good job on Dick and Jane, so it isn't unrealistic to think by 4 they were clicking right along. There is probably someone here on HN who has researched all of this and could tell us more about the steps young minds go through and what works better / worse.