There are two possibilities, they could be second cousins. Or they could be a first cousin twice removed.
Of course, your first cousin's child is related to you; you have ancestors who are also ancestors of your cousin's child. Your first cousin's child is your first cousin, once removed. Your second cousin's child is your second cousin, once removed.
Your first cousin's child is your first cousin once removed (one generation removed).Your first cousin's grandchild is your first cousin twice removed.
Your cousin (if a first cousin) and your child are first cousins once removed.
Your first cousin's child is your first cousin's, once removed. Your second cousin's child is your second cousin, once removed. Your third cousin's child is your third cousin, once removed.
Your cousin's child would be your first cousin once removed. So, your cousin's adopted child would be your adopted first cousin once removed?
The child of your first cousin twice removed is your first cousin thrice (three-times) removed, or your second cousins, once removed.
The child of your first cousin oncer removed is your first cousin twice removed, or your second cousin, depending on which end of the relations you are on..
The child of your first cousin, once removed, is your first cousin, twice removed, if your first cousin once removed is the child of your first cousin. If your first cousin once removed in the first cousin of one of your parents, the child is your second cousin.
Your child and your first cousin are first cousins, once removed to each other.
The child of your First Cousin, and you are First Cousin's, Once Removed.
Your first cousin and your grandchildren (your child's children) are first cousins once removed.
Your first cousin's child is your first cousin once removed. Your children and that child will be second cousins to each other. This poster above is incorrect. If you have the same grandparents as someone on either side, they are your first cousins. Your first cousins once removed would be if your great-grandparents were someone else's grandparents. Your second cousins are if you have the same great grandparents as someone. etc.