Looking for a very small road bike . . .

My daughter wants to ride with me, and we are looking for a road bike. MAX standover of 26", though a little less would be better. She has ridden a Trek KDR 1000, and that fit pretty well. I'd also like to consider a bike with 650cc wheels - if we can find one that fits, it would probably be a little longer before she would outgrow it. We can get a new Trek for $425, but am hoping to find something used for less. Does anyone have a bike their child has outgrown and that needs a new home?