C.O.
It will look like a normal belly button. They are repairing it, not removing it. Since she is a child, i will assume that her belly button is extended and looks like there is a balloon under it? Many doctors will repair the hernia and do their best to make it look "normal" - there is a chance it will be flat. If they do it laproscopically, it might be pulled in.
Please DO NOT give your daughter a complex about her body this young! A plastic surgeon?? Do you think she's going to be a swimsuit model and lose out on jobs because her belly button isn't "perfect"???