Rick, I agree with you and have wondered the same thing since the post was first made. After all, the 4 year old was a great nephew--not the nephew of the couple who allegedly took him on the cruise. Wonder if the O.P can explain in all detail the paperwork that had to be completed before said cruise, as the 4 year old was their nephew's son and as you said, why would someone want to take a 4 year old on a cruise , especially one who was as removed as a great-nephew would be?
I could barely, and I mean barely, just possibly could see me taking my sister's kid on a cruise but cannot see me taking my sister's KID'S kid!--especially 4 year old at that ! Something stinks and it aint the toilet.