Is my maternal cousin's maternal cousin, my cousin?

To determine if your maternal cousin's maternal cousin is your cousin, you need to understand the concept of cousin relationships and how they are defined.

Cousin Relationships

• Cousins are individuals who share a common ancestor that is at least two generations away, such as a grandparent or great-grandparent13.

Degree of Cousinhood

• The degree of cousinhood (e.g., first cousin, second cousin) is determined by the number of generations between the common ancestor and the cousins. For example, first cousins share a grandparent, second cousins share a great-grandparent, and so on13.

Your Maternal Cousin's Maternal Cousin

• If your maternal cousin's maternal cousin shares the same common ancestor as you, then this person would indeed be your cousin.
• Here’s a breakdown:
  • Your maternal cousin is the child of your mother's sibling.
  • Your maternal cousin's maternal cousin would be the child of another sibling of your mother (or another descendant of the same maternal line).
  • Since both you and this person descend from the same maternal line and share the same common ancestor (your maternal grandparents), this person would also be your cousin.

Conclusion

Yes, your maternal cousin's maternal cousin is indeed your cousin, specifically within the same degree of cousinhood as your original maternal cousin. If your maternal cousin is a first cousin to you, then their maternal cousin would also be your first cousin123.