Legal Question in Personal Injury in North Carolina

'Guest' means something very different than 'paying customer'. I'm going to assume you meant your sister was a paying customer not a guest. If that is correct, I don't see any case here at all against the cheap hotel. This would be the same thing as requesting a wake up call because you have a billion dollar deal in the morning - cheap hotel forgets the wake up call - you lose the billion dollar deal - that's your fault not theirs. Since your sister clearly knew the crazy exes mom was after her (hence the request not to give out the room number) your sister should have looked through the peep hole or out the window before opening the door. However, there is very likely a case against the exes mom. You should consult with an attorney ASAP. The type of attorneys that handle these type of cases generally do not charge a fee for a consultation and also generally will handle a case like this on a contingent basis - meaning you will not lay out any money to the attorney, the attorney will only get paid if a settlement or verdict in your favor is reached.