What relationship is your great nephew to your son?

Answer 1

As far as I can make out, Your daughter is your fathers (common ancestor) grandchild, and your grand nephew (not great nephew) is your fathers great grandson.

According to the chart at http://freepages.genealogy.rootsweb.ancestry.com/~gentutor/chart.html

this would make your grand nephew, your daughters First Cousin once removed

Answer 2

Your son and your nephew, or niece, are first cousins to each other.

Your son and your great nephew (the son of your nephew or niece) are first cousins, once removed, to each other.

Your grandson and your great nephew would be second cousins to each other.

Answer 3

Your great uncle is your parent's uncle.

Your great uncle's daughter is your parent's first cousin.

Your great uncle's grand daughter is your second cousin.

Your great uncle's granddaughter is your son's second cousin, once removed.

Answer 4

Your great grand niece is the grand daughter of your niece or nephew. Your niece or nephew is a first cousin to your daughter.

So your daughter and your great grand niece are first cousins, twice removed.

Answer 5

Your great great niece is the granddaughter of your niece or nephew.

Your daughter and your niece or nephew are first cousins.

Your daughter and your great great niece are first cousins, twice removed.

Answer 6

Your daughter and your nephew or niece are first cousins to each other. Your daughter and your great nephew are first cousins, once removed, to each other.

Answer 7

Your granddaughter and your great nephew are second cousins.

Answer 8

Your great nephew is your child's first cousin, once removed.