Documentation Requirements for non-U.S. Citizens leaving from Texas cruise?

[Bella'smom!]

My family is leaving for a Carnival cruise on May 13th from Galveston, Texas. One of the couples on our trip is a couple from Germany. They will be staying in our home for a week prior to the cruise, cruising with us, and then staying in our home for 2 weeks post-cruise.

 

Does anyone know what documentation these German citizens will need, other than their passports?

 

Thanks for any info that you can provide!

[kitty9]

They will need to contact the various countries your ship will be visiting to see if German nationals need visas. If they haven't done this already, and they find out they need visas, it might be too late to get them.