Your brother's or sister's brother-in-law, or your niece's or nephew's other uncle(s) that aren't your brothers.
Jonathon and I aren't blood related, as his sister married my brother, but we are co-uncles to Jack and Caroline.
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Spouse's half-pibling's husband.
My half-co-uncle-in-law is a good person.
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The husband of one's grandparent-in-law's sister.
My co-great-uncle-in-law is a good person.
The son-in-law of one's grandparent-in-law's sibling.
My co-cousin-uncle-in-law is a good person.
Spouse's half-pibling's husband.
half-co-uncle-in-law.