I think this was on one of the "Airline" TV programs during the past few days.
Covered period just after GO had been absorbed by Easyjet.
Child had previously been allowed unaccompanied on GO, to visit father in Spain. Mother thought that the same applied to Easyjet, and booked without reading the "small print". On arrival at airport (Bristol?) was advised child could not travel. Went away and came back with a "friend" she had "discovered" was on same flight. Check-in supervisor thorught she was "pulling a fast one", and refused to accept this arrangement.
At end of program, commentary said that supervisor was correct, and that the "friendship" had been manufactured.