In-laws: who counts and what to call them
Short answerIn-laws are the close family you gain through marriage or partnership. Your spouse’s parents are your parents-in-law, your spouse’s siblings and your siblings’ spouses are your siblings-in-law, and your child’s spouse is your son- or daughter-in-law. Relatives further out are usually described rather than called in-laws.
The three kinds of in-law
| Term | Who it is |
|---|---|
| Parent-in-law | Your spouse’s or partner’s parent |
| Sibling-in-law | Your spouse’s sibling, or your sibling’s spouse |
| Child-in-law | Your child’s spouse or partner |
Beyond in-laws
For further relatives, Family Trees describes the link in two steps instead of stretching the word: your wife’s grandmother, your granddaughter’s husband. The partner of a blood aunt, uncle, niece or nephew is an aunt or uncle by marriage.
Your spouse’s cousin is not usually called a cousin-in-law in formal genealogy, though many families say it. The app writes “wife’s first cousin”.
Partners and exes
In-law terms come from partnerships that still stand: married, partners or separated. After a recorded divorce, the former spouse is an ex-husband or ex-wife and their family is no longer named as in-laws.
Let Family Trees name it for you
Every parent link in Family Trees is birth, adoptive, step or foster, and every couple is married, partners, separated or divorced. From that, the app names each relative in plain words on their page and under How are they related?, including half, step, foster and in-law relations. It’s free for up to 100 people.
Questions
Is my brother’s wife my sister-in-law?
Yes. Your sibling’s spouse and your spouse’s sibling are both siblings-in-law.
Is my spouse’s sibling’s spouse my in-law?
Not formally. Your wife’s brother’s wife has no standard term in English; many families still say sister-in-law. Family Trees calls them family without forcing a label.
Do unmarried partners have in-laws?
Many families use the words anyway. Family Trees names a partner’s parents as parents-in-law for partners as well as for married couples.