Definitely keep reading to him. My DS who is 4 is taking to reading like a duck to water. I got hold of the Ladybird Key Word series (you know.. the Peter & Jane books) and they are pretty much sight words that they learn.. I think it's based on the 100 most common words.

I've also got him doing the Reading Eggs program on the internet.. he LOVES it and wants to do it every day LOL. This has definitely got him understanding the concept of reading.

I haven't really done anything in particular with DD yet (she's a couple of months younger than your DS by the looks) because she hasn't shown a real interest in it yet. Loves books etc, but isn't asking what things say or sounding things out yet. Once she does that I'll get going with more "teaching" stuff. She watches DS on his program all the time tho, so she'll probably pick it up quickly too.

I'm not sure that reading would be something that would need to be 'untaught'.. as you either recognise words or not, or know how to sound them out or not. I can understand writing of letters etc can be taught 'wrong' but I would think if they can read, then they can read. Apparently I was reading fluently before I started school, mum reckons she didn't 'teach' me.. just read to me a lot and did those Peter & Jane books with me. I think if they are ready to read, then they will learn it quickly and it won't be something you have to 'hothouse' them with, cos as you say, it's the next step to their interest in letters and books.

Have fun with it