Did you happen to grasp that she is a 15 yr old coming back from Disney. Maybe you can give her a break since she won't be 18 for 3 more years. God forbid if she is an adult and requests a hot meal on a plane. The horror....
Her mother needs to be preparing her to deal with that. Prepared or not, adult accountability is going to smack her in the face
Get this: When she's an adult, who's going to prevent her "having a meltdown"? What's going to happen when she can't handle herself, and becomes a threat to herself or others? What is her mother doing ... NOW ... to help her avoid that sort of thing?
Oh, yes:
Her mother is HINDERING such preparation.