A passport or original birth certificate and picture ID
No, but, It's recommended.
You will need a passport
It's never a bad idea to have a Passport, specifically if your cruise has ports of call out of the US, while in a foreign country you need to be able to produce a passport to local authorities, if required.
better have it
You only NEED a passport if something happens and you have to take a flight to catch up with the ship or return home (medical emergency, missed all aboard time). Otherwise, as others have stated, a state issued birth certificate with your full name as registered with Disney (married name change can cause issues here) works for reentry to the US after the cruise.
No, a valid state-issued birth certificate and state ID will work, but the passport is the best option. Children only need a state issued birth certificate.
Yes, you need a passport.
They told us it was preferable, but no you do not need it. Proof of citizenship or passport was all they required. I used my passport and my children's birth certificates. Hope this helps :)
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