I cried the first time my daughter flew as an un-accompanied minor.
She flew to MSP with my Father and was gone for 2 weeks. Didn't phase me a bit. When her planed landed back in PHX and as I stood at the gate waiting for her to come down the jetway the tears just started flowing and would not stop. I was realizing how indpendant she was becoming and how much longer she wouldn't need me around.