Is this a road bike or mtn bike?
There sometimes is a little lever at the brake itself that allows for some opening/closing movements of the brake pads. You could try to open it up a little bit. It also could be that the cable just needs to be re-adjusted. A little technical if you don't know much about bikes. I would say to DIY, but since this is for your daughter it might be best to take it to the local bike shop and ask them for help. Since none of us can look at what you are dealing with, it would be hard to say exactly what is wrong and since you don't have much experience to describe things, the bike shop might be the safest solution. After all, it is your daughter's safety we are talking about here.