Sorry, no, there is no way to get rid of that '1' it's there until you do update I'm afraid. You will get used to it after a while, well at least I did!
I've been staring at that 1 since long before iOS7 dropped. Re. the accidental update, iirc you have to be plugged into an outlet to update; if she's like most people she's not using it while charging so the risk would be minor.