ESH- former professional nanny. She should never have let mom inside without letting you know. That rule is in every contract I have had. But I'm guessing it wasn't in your contract and possibly that you don't even have a contract which leads to your responsibility in all of this- you chose a young college student who's babysitting as a side gig but expect nanny level professionalism and then fired her at the first offense. I can totally see why someone like her wouldn't get why it was no big deal when it's her mom. I would have drawn up a contract and then if it happened again, fired her but this went 0-60 real quick. You had EVERY right to be upset and concerned but you also need to take into account that you don't just get WHAT you pay for, you get WHO you pay for. This is remedied now that you've hired someone new but if it's another student doing side gigs, expect this might come up again and you can handle it bettwr