Your sister-in-law's grandson is your great nephew.
cousin
He has one son called Edson.
Sons would be plural and son's is possessive. Tickyul
He has a son called Zac and a daughter called Liberty!
dappys son is called gino
Enzo Ferraris son was called Dino
because they are the sons of the people
basiclly there called brothers .-.-.-.-.-.-. basically* for one... and two no, they wouldn't be called brothers. If it was their parents sons then yeah, but if it's the sons of brothers then they'd be cousins. That's practically like saying one brother got married and had a son, then the other did too and had a son as well. The relation of the sons would be cousins.
he has two sons named joey and jakob
You do you call your sons's son your "grandson" !
He had three sons: Damerei, Carew, and Wat (Walter)
She had two sons ... Sean Preston and Jayden James