According to the British Laws, the grandson would be the king. Other monarchies inherit under different rules. It depends on the particular country.
Your first cousin's grandson is your first cousin, twice removed. Your second cousin's grandson is your second cousin, twice removed.
The grandson of your father's first cousin is your second cousin once removed.
Your first cousin's daughter is first cousin once removed to your grandson, and he to her. Your second cousin's daughter is second cousin once removed to your grandson, and he to her.
Your grandson and your sister's grandson are second cousins to each other.
Second cousin, once removed. Your parent on that side would be a second cousin to the grandson.
First cousins once removed. Your child and your nephew are first cousins and there is one generation difference.
they would be first cousins once removed. this is because the grandchild's parent would be your son's first cousin and because its the cousin's child, its once removed
Great nephew. Your children are the first cousins of your niece and your children would be first cousins once removed. Your grandchildren and your niece's child would be second cousins.
There is no proper term for this particular familial place. I would suggest just his name or your step-father's grandson.
Your great aunt's great granddaughter is your second cousin, once removed. (Your great aunt is the sister of one of your grandparents and your great aunt's granddaughter is your second cousin.)
Your cousin's child is your "first cousin once removed". If you were to have children, your child and your cousin's child would be second cousins. The son of your cousin's son would be your first cousin twice removed. Look at it like this: you * your cousin * ** your cousin's son (your cousin once removed) ** *** your cousin's grandson (your cousin twice removed)
Your great-grandmother's sister's grandson is your second cousin once removed.