Which relatives are included in the first degree by blood?

• A. Father, mother, and children.
• B. Spouse and spouse's parents.
• C. Grandparents and grandchildren.
• D. Uncles and aunts.

Answer: (A)

First-degree by blood covers the closest direct blood connections in a straight line of descent or ascent. Your parents and your children fall in this category because they are the nearest relatives connected to you by blood, one generation apart.

Spouse and spouse’s parents aren’t blood-related; they’re related by marriage, not by biology, so they don’t count as blood relatives in the first degree. Grandparents and grandchildren are a generation farther away in the direct line, so they’re considered a second-degree relationship. Uncles and aunts are collateral relatives (they’re siblings of your parents), which places them beyond the first-degree by blood.

So the closest direct blood relatives are your father, your mother, and your own children.