Feel like you need a calculus equation to figure out exactly how you’re related to so-and-so from your mom’s great-grandmother’s brother’s line? Let us simplify things! What kind of cousins you are depends on the most recent ancestor you share with your relative. First cousins share grandparents. Second ones share great-grandparents, third ones share great-great-grandparents, and so on. Add a “great” for each generation away from the common ancestor.

Things get trickier when you’re talking about being “removed.” Each “removal” signifies one generation of difference between the two. Your first cousin’s child is your first cousin once removed. Your first cousin’s grandchild is your first cousin twice removed.

Meet Ann and Bea. They met at a genealogical society meeting and are trying to determine how they’re related. Can you help them figure it out?

4 basic steps to follow:

1. Identify the most recent ancestor.

For Ann and Bea, let’s say it’s James Eugene Harding, born in 1850.

2. Determine each person’s relationship to that ancestor.

Ann and Bea determine that James is Ann’s great-great-grandfather and Bea’s fourth-great-grandfather.

3. “Equalize” the cousins at the level of the one closest to the common ancestor.

Equalizing the them at Ann’s level would make them third cousins.

4. Add one “removed” for each difference in generations between the them.

Two “greats” separate Ann and Bea—they’re third cousins twice removed.

Figuring out these relationships takes some practice. If you are looking into becoming a professional genealogist, valuable skills like these matter! Luckily, there are plenty of resources here on our website. Download our free PDF relationship chart, or use this handy cousin calculator to start. You can “count on” becoming an expert in these calculations in no time!

More from Family Tree

• Counting Cousins: How to Calculate Cousinhood
• How to Use MyHeritage DNA Matching
• 10 Ways to Connect with Distant Cousins

Shannon Combs-Bennett is a Qualified Genealogist based out of Northern Virginia. She holds a PLCGS in American Studies from the National Institute for Genealogical Studies. Shannon lectures and writes on a variety of genealogy topics. Her book, Genealogy Basics in 30 Minutes, won the IBPA Benjamin Franklin Silver Award in 2017. Shannon is as a columnist for the Federation of Genealogical Societies magazine FORUM, and the Southeast Regional Director for the International Society of Family History Writers and Editors. Follow her on Twitter at @tntfamhist.

A version of this article originally appeared in the May/June 2015 of Family Tree Magazine.

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