Traveling by plane with a baby?

I'm planning on going to visit my family in Costa Rica with my son who will be 4 months by the time I go. So I was wondering if anyone has tips on traveling with babies? Like how do I bring his formula/breast milk? Thanks ladies

About Crisel Casanova
Birth: October 31
On since: Mar 8, 2014
Happily married for about a year and a half, and im a new mom. I live in Puerto Rico, however I'm from Costa Rica and dont know a lot of people here except my husbands family. I hope I can make new friends and share stories with other moms.