For example, every single new sibling talks about a lawsuit right off the bat. We have to explain to them each time that: The clinic went under, Lippert (the IVF technician/bio father) died in 1999, and the doctor overseeing it killed himself and destroyed the records. There is no lawsuit possible because there's nobody to sue, but also we'd have to prove some sort of damages, and being alive doesn't really count, for most of us anyway :D.
Most of us who knew early on are also a bit weary of discussing it with new siblings in general, and many of us have wildly different ideologies like politics and religion, so conversation gets weird fast at any gathering or chat group. Also some get really reactive and get really weird with us when we reach out before they usually completely shut us out. Some have been more intense in that regard.
2. GSA. https://en.wikipedia.org/wiki/Genetic_sexual_attraction. It's super real and has affected more than one sibling. This can be very intense, and intense attractions can lead to intense reactions. I don't know how much more there is to say about this other than reading up on it, but there are lots of examples of this and it's quite common in these scenarios.
Obviously this can lead to things like accidental (or purposeful) relationships (which is it's entirely own topic of discussion, esp with regards to marriage etc), or genetic birth defects of their kids. There aren't any examples of extremes of these in my situation that I'm aware of so I don't have any crazy stories, but you can see where it could lead.
Those are the big ones.
It can be quite pleasant too, and some of us have become close friends, I shouldn't leave that part out.