It would be great if she rode with you, especially with 4 kids. But just remember that she may just not want to ride. Buying her a bike doesn't mean she'll ride it. Maybe a better approach would be to take two kids at a time to ride with you, and she takes the other two. Maybe that way, she'd decide on her own that she'd rather have a bike so that the family can bike together. But it'll have to be her choice for it to work.