Don't start bringing relatives into the equation ... inbreeding is what is responsible for this strange behaviour in the first place.
A trip to the seaside is enough to demonstrate that the earth is curved, not least because you can SEE it from left to right on the horizon.
Also a boat sailing out to sea disappears bottom first, mast last. A boat on a level sea would just get smaller but with ALL parts visible until it was a dot.
Seemples!
Next!
All the boats I have ever observed could have been related to the Titanic, I suppose!
