In the past few weeks I've come across two people that I work with that know people with Chiari malformation. One of my coworkers has a friend who has two young children with it--one is severly affected, wheelchair bound, and the other has no symptoms at all. It really runs in the family, as this woman's sister has a child with it as well, and he is severly affected like his cousin is.
I have another coworker who has a daughter in her 20's that was just diagnosed and is now scheduled for surgery.