Cleft Lip / Palate Support Group
Cleft is a congenital deformity caused by a failure in facial development during gestation. It can be treated with surgery shortly after birth with highly successful results. Cleft occurs in somewhere between one in 600 and one in 800 births. Cleft occurs in several severities and is divided in two major categories: cleft lip and cleft palate.
Everybody's at different levels of comfort with it. As far as approaching the 18-ish girl you saw, I would say that it is always okay to affirm somebody's worth and try to improve their day. Sometimes "are you ok?" can be an awkward question though, even if the person looks down. I actually had a very awkward moment last week with my boss (who is also a friend outside of work) when he asked if I was okay in a public part of the store. I really wasn't, had a lot of stress going on with my school and work schedule, and I think the ensuing conversation in private might have been less awkward if he hadn't surprised me with that question like he did. So, tact is very important.
I used to think there would be an issue of being embarrassed for "settling" for another cleftee individual when we were seen together. But, I feel confident enough now in my, er, cleftee identity that I don't think it would have to be an issue. It would just be a matter of shared experience, and I'd have no problem telling anybody with a case of the snickers why it makes perfect sense for them to go f**k themselves, figuratively speaking...
I did some research for a presentation on cleft last semester and I learned some figures about genetics. This was my primary source: http://cleftline.org/docs/Booklets/GEN-01.pdf. Depending on the occurrence of cleft in your family tree, your chance of having a cleftee child could range from 2% to 12%. It doesn't talk about the chances for two parents with clefts, though. I think it might be higher, as I have heard of entire families who have the condition. Personally, I have always been open to adoption, but, if I had a stable relationship with another person I could see myself being okay with having a biological child, even if my partner had a cleft too. Under stable and positive conditions of support, I think a cleftee child can be raised with minimal negative issues. But, I doubt that is the path I will wind up taking.