How many third cousins do I have?
So to find out how many third cousins youd have (d=3) if your family averaged having two children per couple (n=2), it would be (2-1) 23 * 23 = 64. The number of fourth cousins youd have (d=4) if your family averaged three children per couple (n=3) would be (3-1) 24 * 34 = 2592.
How do you figure out 3rd cousins?
First cousins share a grandparent (2 generations) Second cousins share a great-grandparent (3 generations) Third cousins share a great-great-grandparent (4 generations)
Why do I have so many 4th cousins?
Obviously, the exact number of fourth cousins that you actually have depends on how many children your great-great-great grandparents had, how many children their children had, and so-on and so-on.
Are fourth cousins blood related? When people ask if two people are “blood related”, what they might be asking is if fourth cousins share DNA. You will only share DNA with about 50% of your possibly 940 4th cousins. In other words you are related genealogically to all of your fourth cousins but you might not share DNA.