My son, in his late 20s and living on the west coast, has become friends with a high school friend of my my daughter who also lives out there (she's early/mid-20s). At this point, they seem to be platonic, but definitely enjoy hanging out together. Parents and sibs on both sides have our fingers crossed -- they would be a great match.

I dated my older brothers' friends (brothers were twins) when I was in my 20s. My brothers didn't like it but their friendships survived and it's never been awkward. I could see how it might be but I was never deeply invested in the 'relationships'.

My kids are older teens and have not yet dated each other friends although their friends have dated. They're learning to navigate the situations.

I dated the sister of someone I'd previously dated. I guess the parents weren't that happy about it but it didn't seem to create too much friction between the two sisters except when the one first found out.

Not my kids, but my parents! Mom and her sister dated 2 best friends, both got married, and one married 61 years, the other (my aunt) passed away a few years ago, but also a very long and happy marriage.

If my aunts husband's best friend hadn't dated his girlfriends sister, I wouldn't be here 🙂

My dad was my uncle’s good friend in law-school. My dad stayed with my maternal grandparents (i.e., my uncle’s parents) when interviewing for jobs and met my mom.

My oldest DD dated one of DS's best friends. I think it was only for a few months - maybe half a year. Eventually they broke up and everything's fine. Not at all awkward.

My close friend met her wonderful husband because he was friends with her older brother. It can happen.

Oh boy. I have b/g twins and this did happen. My DS was very against this happening but it was with one of his best friends, who had been crushing on my DD for years. The time was finally right for both of them and they started dating. It was an absolute disaster and they broke up four months later. It put my DS in a very awkward position between the two of them, as the break up was NOT easy or amicable. My DD is no longer allowed to date any of DS's friends, haha, nor does she want to.

I am wondering how common this is once siblings are older. I could see siblings who are in the same city hanging out and dating each other’s friends. Might be awkward if things don’t work out, but it also seems like a good way to expand your pool of potential mates.