What is my sister-in-law's husband to me?
There's no single English word for him — which is exactly why the question gets asked. If your sister-in-law is your spouse's sister, her husband is your co-brother-in-law, the label genealogists use. If she's your brother's wife, her husband is your brother himself, so the question only bites on the spouse's side.
Relationship
Co-brother-in-law
English has no single formal word for this relative — “co-brother-in-law” is the label genealogists use.
- You
- Your sister-in-law
- Her husband
From the other side, you are their co-sibling-in-law.
This connection runs through a marriage, not a shared ancestor, so the ancestor chart can't draw it.
The calculator below works out blood relationships through a shared ancestor — use it to explore the rest of your tree.
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This relationship sits outside the shared-ancestor model, so the card above carries the answer and the calculator opens in its default state. Work out any blood relationship with it, or open the full relationship calculator.
FAQs
Is my sister-in-law's husband my brother-in-law?+
Not strictly — brother-in-law covers one marriage step. Two marriages separate you here, so the genealogical term is co-brother-in-law.
Who am I to my sister-in-law's husband?+
His co-sibling-in-law — the chain reads the same from both ends.
Does the calculator store my family details?+
No — it runs entirely in your browser. Nothing you enter is uploaded or saved on our servers.
Start with one relative and see what comes back.
Add what you remember and AncestorIQ searches for the rest. Free to build your tree for as long as you like.
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