Thanks for the prompt response. I do not want to pay for passports if we can just get by with the birth certificates. I've called Travelocity and NCL and both companies say that birth certs are ok for the minors. I just want to get an opinion from someone who actually experienced some hassles at the port because they did not bring passports for the kids. Any suggestions as for things we can do as a family while on shore or on the ship?