Your son and your 1st cousin's child are 2nd cousins.
Your first cousin is your son's first cousin once removed.
Your son and your nephew are first cousins to each other. Their daughters are second cousins to each other.
Any child of your first cousin, is your "first cousin once removed". Indicating they are 1 generation from being your first cousin. Your children & the children of your first cousin would be "second cousins".
Cousine
Your sons children and your daughters children are First cousins. The idea is that First cousins share a grandparent, second cousins share a great-grandparent, third cousins share a great-great-grandparent, and so on. The degree of cousin relationship i.e. "first," "second," etc. is used to denote the number of generations between two cousins and their nearest common ancestor. Now, a term "removed" is used to refer to the number of generations separating the cousins themselves. So your first cousin once removed is the child (or parent) of your first cousin. Your second cousin once removed is the child (or parent) of your second cousin. And your first cousin twice removed is the grandchild (or grandparent) of your first cousin. etc. Thus in this case they are first cousins once removed.
Nephews are the sons of your brother or sister. Therefore nephews who are not brothers to each other are first cousins to each other.
The sons of your father's sister are your first cousins.
Your granddaughter and your sister's grandson are second cousins.
Your mother's sister's children, sons or daughters, are your first cousins. The children of first cousins are second cousins to each other. That is the relationship between your children, or either sex, and your first cousin's children, of either sex..
Your dad's nephew is your first cousin, his children are your first cousins once removed.
Wat the heck in this question yaar? its maternal uncle. you are uncle your son is first cousin to your sisters his aunt sons or daugters a : a child of one's uncle or aunt b : a relative descended from one's grandparent or more remote ancestor by two or more steps are cousins and when those sons and daughters have kids they become second cousins etc.
Your mother-in-law's brother and his children are not related to you.He is your childrens' uncle and his children are first cousins to your children.