Hi J.,
My girlfriends husband did the same thing to her little girl. She had a huge bump on her head but everything was fine.
As far as the concussion, it's always better to be on the safe side. I would take your daughter in, if nothing else it will give you and her Grandpa some peace of mind.
Best Wishes,
Good morning DeAna,
I would/have checked the carseats like luggage before, wrapped in a garbage bag. Even if you "gate check" most likely the car seat will end up below with all the other luggage.
Let the steward/stewardess know this is the first time your little ones are flying they have a cute little certificate and flying wings to give you for their scrap book.
Good luck and have a wonderful trip!
C. Roeschen
The Trinity Group
Keller Williams
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