Third cousin twice removed.
Your father's first cousin's child is your second cousin. Your father's second cousin's child is your third cousin. Your father's third cousin's child is your fourth cousin. and so on.
Your cousin's brother is also your cousin. His child is your cousin once removed. For example, if your first cousin has a child, that child is your first cousin, once removed. If your third cousin has a child, the child is your third cousin, 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 first cousin's child is your child's second cousin. Your second cousin's child is your child's third cousin. Your third cousin's child is your child's fourth cousin. and so forth
Your dad's second cousin's child is your third cousin.
Your first cousin's child and your child are second cosins. Your first cousin's grandshild and your child are second cousins, once removed. Your second cousin's child and your child are third cousins. Your second cousin's grandchild and your child are third cousins, once removed.
your 2nd cousin, or maybe your 2nd cousin once removed.
Your child and your second cousin's child are third cousins to each other.
The child of your mother's first cousin is your second cousin. The child of you mother's second cousin is your third cousin.
Your second cousin's child is your second cousin, once removed. Your second cousin's child and your child are third cousins to each other.
Your child and your first cousin's child are second cousins. Your child and your second cousin's child are third cousins to each other.
If your father's third cousin is an uncle because his brother or sister has a child, then that child and you are fourth cousins.If your father's third cousin is an uncle because his wife has a brother or sister who has a child, then that child and you are not related to each other.