Explanation of Family Relationships (2024)

Here is an explanation of the English-language conventions for naming family relationships, and some technical facts about ancestry.

Relationship Chart

The best tool for understanding the confusing relationships of cousins is a relationship table. On WikiTree our Relationship Finder will do the work for you — the following is just for illustration.

Common Ancestor
	parent	grandparent	great grandparent	2nd great grandparent	3rd great grandparent
parent	sibling	niece or nephew	grandniece or grandnephew	great grandniece or grandnephew	2nd great grandniece or grandnephew
grandparent	niece or nephew	1st cousin	1st cousin 1 time removed	1st cousin 2 times removed	1st cousin 3 times removed
great grandparent	grandniece or grandnephew	1st cousin 1 time removed	2nd cousin	2nd cousin 1 time removed	2nd cousin 2 times removed
2nd great grandparent	great grandniece or grandnephew	1st cousin 2 times removed	2nd cousin 1 time removed	3rd cousin	3rd cousin 1 time removed
3rd great grandparent	2nd great grandniece or grandnephew	1st cousin 3 times removed	2nd cousin 2 times removed	3rd cousin 1 time removed	4th cousin

To use this chart, start by determing the first common ancestor between two people. Next you name the relationship between the common ancestor and the first person, and between the common ancestor and the second person. For example, for you and your aunt, the first ancestor that you share is a grandparent to you, and a parent to your aunt.

Follow across the horizontal (x-axis) columns to find the name of the relationship between the common ancestor and the first person. For you, this is a grandparent so it would be the second column.

Follow down the vertical (y-axis) rows to find the name of the relationship between the common ancestor and the second person. For your aunt, this is a parent so it would be the first row.

Where the column and the row intersect is the name of the relationship between the first person and the second person. You already knew your relationship with your aunt, but as you can see, the table tells you that you are her niece or nephew.

Deeper Ancestry

To make it easy to read, the table above only has five generations. WikiTree's Relationship Finder searches 25 generations. To go even deeper, this Cousin Relationship Calculator will show 100 or more. The page also has some handy definitions.

Half-Relationships

The table above considers the first common ancestor, singular, not the first common pair of ancestors.

Therefore, it doesn't account for "half-" relationships. For example, if you share a common father with someone they are your sibling. If you don't share the same mother, some would call you have a half-sibling.

Relationships by Marriage

The table above only considers "blood" relationships, not relationships through marriage.

Despite having no common ancestry, the following are still family relationships:

• Spouses, i.e. husbands and wives.
• In-laws, i.e. the family of your spouse.
• Aunts and uncles through marriage.
• Step-children, step-siblings, step-parents, step-grandparents, etc.

WikiTree's Connection Finder will find relationships through marriage, but only out to ten degrees of separation.

Number of Ancestors

You have over two thousand direct ancestors in just ten generations. Here's how the numbers work.

1. Two parents (1 mother + 1 father = 2)
2. Four grandparents (2 grandmothers + 2 grandfathers = 4)

• Subtotal: Six ancestors in two generations (2 + 4 = 6)

• Subtotal: 14 ancestors in three generations (2 + 4 + 8 = 14)

• Subtotal: 30 ancestors in four generations (2 + 4 + 8 + 16 = 30)

• Subtotal: 62 ancestors in five generations (2 + 4 + 8 + 16 + 32 = 62)

• Subtotal: 126 ancestors in six generations (2 + 4 + 8 + 16 + 32 + 64 = 126)

• Subtotal: 254 ancestors in seven generations (2 + 4 + 8 + 16 + 32 + 64 + 128 = 254)

• Subtotal: 510 ancestors in eight generations (2 + 4 + 8 + 16 + 32 + 64 + 128 + 256 = 510)

• Subtotal: 1,022 ancestors in nine generations (2 + 4 + 8 + 16 + 32 + 64 + 128 + 256 + 512 = 1022)

• Subtotal: 2,046 ancestors in ten generations (2 + 4 + 8 + 16 + 32 + 64 + 128 + 512 + 1024 = 2046)

However, you might not actually have two thousand different ancestors in these ten generations. This is due to what is called "pedigree collapse".

Autosomal DNA Connections

The following is a rough illustration of who is included in our autosomal DNA test connections.

Note that this does not exactly match our program. This illustrates five steps of blood relationship, but our program does eight steps: up to sixth great grandparents and out to third cousins. See Help:DNA Test Connections for more information.