By comparison with having a child with a more distant relation, there would be an increased chance that the child would have an inherited, genetic, condition or disease. This depends on whether there is a recessive for one of those conditions in the family. There is no guarantee of a problem, and no guarantee there will not be a problem. But even in marriage between "completely unrelated" people, there is always a chance that the children will have an inherited disease or condition. It is just a matter of how large those changes are.
The nephews of your first cousin once removed, like the children of your first cousin once removed, are your first cousins twice removed.
Your first cousin and your children are first cousin, once removed. Your second cousin and your children are second cousins, once removed. Your third cousins and your children are third cousins, once removed. And so forth.
Your grandmother's first cousin is your first cousin, twice removed. The children of her first cousin are your first cousins, once removed.
Your first cousin's children are your first cousins, once removed. They are your children's second cousins. Your second cousin's children are your second cousins, once removed. They are your children's third cousins. And so forth.
Your first cousin's daughter is your first cousin, once removed, and her children are your first cousins, twice removed.
Your daughter is first cousin once removed to your cousin. Your daughter is second cousin to your cousin's children. Your cousin's children are first cousins once removed to you
Your parent's first cousin's children are your second cousins. Your children and your second cousin's children are third cousins. Your children and your second cousin - or likewise you and the children of your second cousin - are second cousins, once removed. You and your parent's first cousin are first cousins, once removed.
Your first cousin's child is your first cousin once removed. Once removed means one generation apart. Your cousin's grandchild would be your first cousin twice removed--two generations.
Yes, your "first cousin once removed" is either :your children's "first cousin twice removed" -- if your "first cousin once removed" is the first cousin of your parent, oryour child's "second cousin" if your" first cousin once removed" is the child of your first cousin.
The children of your first cousin twice removed are your first cousins, thrice removed - or three times removed.
First Cousin, twice removed.
Your first cousin's children are your first cousins, once removed. Your second cousin's children are your second cousins, once removed.