My wife mixed reading with spelling, starting when each boy was four. She'd work on simple letter sounds, then make a list of 'rhyming' words: sat, pat, fat, cat, mat and so on. They would sound out the list, then come up with some more, even some silly ones like dat or jat. Hilarious! for a four-year-old.

So they learned to read without really trying. It would take a few weeks of evening 'spelling time' and that was it.