We don't devote much daily time to "school work" here, and pretty much none at all to reading instruction. Our literacy time is all taken up with read-alouds, story-telling, and, this month, poetry. But nevertheless, while I was doing the dishes the other day this is how the boys were occupying themselves in the other room.
A couple different things going on. Like me Harvey doesn't want to work on something unless he's good at it, and unless he has a good reason to; he also likes to be helpful, especially when he doesn't have to work too hard. Practicing reading with me is frustrating and annoying to him—totally understandably! But he's spent a couple hours a day with his nose in a book every day for at least a year, slowly figuring things out by himself. So when I ask him to read to his brothers while I do some other work, he doesn't see a pointless difficult task, he sees a chance to be useful while showing off a developing skill—and being the focus of uncritical attention!
Don't tell him, but it's all great practice. He's moving up to comic books now—whether they like it or not!—and apologized to me for not being able to do the voices. I pointed out how well he reads with expression from the books he knows better; I'm sure the comic books will come in time too. His audience is delighted either way.
Of course, remember: he still doesn't know how to read.