I need your advice!

I need your advice! I am going to visit my sister in Oklahoma in a couple days and am flying by myself with Hailee. I am so scared! She can't stand to sit still! Even for the one hour in sacrament meeting we have to let her play on the ground. There is no way she will just sit in my lap for the flight! Plus I got my ticket too late so I am in a middle seat in between two people, I hope they're nice! Do planes make babies sleep like cars do? Should I bring my boppy pillow to hold her on? Benadryl? Any other advice? Let me know what you think!