Ok I have a question for, my brother in-law and sister in-law are flying to PBI next week and they will be escorting a friend of one of my daughters so a non-relative. When they check in, the parents of the girl will be with them to check her in, but what about i.d.? I read in the T.S.A. web site about adults needing i.d. but this is all being done so her parents don’t have to pay a fee of $100 to fly her as a UM. Any thoughts? I have 0 pax service backround, unless it involves a manifest. 
Simple answer, contact the airline they will be flying on.
The not so simply would have me thinking that if she gets checked in with her parents, TSA aren’t going to say anything (at least that’s not there job, but we all know how that goes) as long as she has some kind of ID & a boarding pass.
I still would probably lean on calling the airline.
If you call the airline dont give them too much detail w/names and dates as they will note your conversation in the computer system. So if you try to ask again to see if you’ll get a better answer they’ll know you were already told . But if they say its no problem and there is no fee then give them the specifics and ask them to make a notation. But, if the child is traveling with the other people on the same flt they shouldnt be considered a UM as they would be accompanied.
First thank you for the ideas. I was thinking about this after the fact, I really shouldn’t sweat this to much…it really isn’t my problem…it is my brother in law sweating this issue…love him to death but they’ll figure it out