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The Family Relationship Chart

Understanding the cousin tree chart.

Uncovering relationships with different ancestors is an exciting process for family history researchers. But, when you take a look at the big picture of your family tree, you may be unsure how some of the connections work. For example, which common ancestor do you and your fourth cousin share? How many people do you share great-great-grandparents with? 

Questions like these are common, especially when tracing all of your cousins through the generations. So, it’s worth taking the time to learn more about these relationships. Here at the Irish Family History Centre, on-site at EPIC The Irish Emigration Museum, we’ve created an easy to understand cousin tree chart and answered some of the most common questions about your family tree below.

For further assistance on discovering the intricacies of your family tree, book in a consultation with us below.

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What Is a Relationship Chart?

Through a family tree chart, cousins can see a visual map of how they are related. Use our cousin tree to understand these family connections by following the steps below.

  • Use the top row to find your relationship to the common ancestor
  • Use the far-left column to find your family member’s relationship to the common ancestor.
  • Follow your column down and their row across until they meet.
  • The box where they meet shows your relationship to that family member.
Family member’s relationship to common ancestorChildGrandchildGreat-grandchildGreat-great-grandchildGreat-great-great-grandchild
ChildSiblingNiece/NephewGrandniece/GrandnephewGreat-grandniece/Great-grandnephewGreat-great-grandniece/Great-great-grandnephew
GrandchildNiece/NephewFirst cousinFirst cousin once removedFirst cousin twice removedFirst cousin three times removed
Great-grandchildGrandniece/GrandnephewFirst cousin once removedSecond cousinSecond cousin once removedSecond cousin twice removed
Great-great-grandchildGreat-grandniece/Great-grandnephewFirst cousin twice removedSecond cousin once removedThird cousinThird cousin once removed
Great-great-great-grandchildGreat-great-grandniece/Great-great-grandnephewFirst cousin three times removedSecond cousin twice removedThird cousin once removedFourth cousin

Family Relationship Chart Questions Answered

This genealogy relationship chart can help you determine the links between members of your family. However, you may still have some questions about these connections. Here are answers to some common questions we receive about family relationships.

What Does First Cousin Once Removed Mean?

The term ‘first cousin once removed‘ means that this cousin is one generation separated from you on your family tree. So, while your first cousin belongs to the same generation as you, your first cousin once removed would either be your parent’s first cousin, or your first cousin’s child. 

This also means that you each have a different relationship with your common ancestor. For example, if your common ancestor is your grandparent, they would be the great-grandparent of your first cousin once removed. 

What Does Double First Cousins Mean?

The term ‘double first cousins‘ refers to children who are first cousins on both their mother’s and their father’s side of the family. For example, say Mark and Susan have a baby, and then Mark’s brother Dan has a baby with Susan’s sister Jill. The babies of these two couples are double first cousins. 

What Does Second Cousins Mean?

If someone is your second cousin, it means you share a great-grandparent as your common ancestor. This differs from first cousins, who have a grandparent as their nearest common relative. The ‘second’ in second cousins refers to the number of generations removed from the common ancestor. 

How Many Generations of Common Ancestors Can You Trace Back?

If you’re using an autosomal DNA test for ancestry research, like 23andMe or AncestryDNA, you can typically trace between five to seven generations back on your family tree. There are other DNA tests that can identify ancestors up to several thousand years back. These include Y-DNA tests and mitochondrial DNA tests. 

Are Third Cousins Blood-Related?

Yes, your third cousins are considered your relatives, as they have a spot on your family tree. You will also likely have a detectable DNA relationship with your third cousins. However, if you do share DNA, it will be a very small amount: only around 0.78 per cent. 

Get Help Identifying Your Family Tree with Irish Family History Centre

The Irish Family History Centre can help you piece together your own genealogy cousin chart to find new members of your family tree. Our experts have worked with countless families to fill gaps and connect with relatives near and far. 

Contact us today to develop your own second cousin chart and begin making discoveries about your lineage. We’ll create a plan to help you make the most of your family history research.

Photo by Eilis Garvey on Unsplash

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