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AIBU?

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Is it weird that my younger brother is dating my wife’s younger sister?

77 replies

kfyuy · 07/09/2026 10:34

Me and my wife are both in our mid40s and have been married for 18 years. We have 3 kids.

I have a younger brother (38) and younger sister (42). My wife has an older brother and sister, and a younger sister who is 38.

Anyway… my younger brother and my wife's younger sister have apparently been dating for a while. Both have children from previous marriages my brother has 2 kids and her sister has 3. All the children are under 10 and roughly similar ages.

I only found out yesterday at dinner, when my wife casually announced that they were a couple. They were both there too. Apparently they're quite serious and are planning to get married.

And yes, I realise everyone involved is a fully grown adult and they're not doing anything wrong. I genuinely want them to be happy.

But I can't help thinking… isn't this a bit weird?

My little brother potentially marrying my wife's little sister means our families are suddenly going to be even more intertwined. We'd effectively become in-laws twice over, and our kids would have their uncle married to their aunt.

Maybe I'm overthinking it, but finding out about it at a family dinner, and being seemingly the last person to know, has left me slightly bewildered!

OP posts:
Bellabelloo · 07/09/2026 10:38

I have friends whose siblings also married and they have such a close knit family unit. It’s lovely.

PinkyFlamingo · 07/09/2026 10:36

You are overthinking it.

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