We'll be traveling during Christmas. If I pump and do not feed DS all of the pumped milk, I'd like to bring it back with me. The flight is 3 hours long, and I'm guessing we'll be at the airport 1.5 hours before and an hour 1.5 to deboard and drive home, so a total of approx 6 hours of travel time?

What's the best way to keep the milk cold? Will they allow a frozen ice pack through security (the ice pack that came with my Medela pump set)?