Turns out a nineteen year old "friend of a friend" dropped off a three day old little girl at her house, quickly saying "my friend said you were a good babysitter I'm going to a party bye" before running off - never to return. Three months later she completed adoption proceedings - her live-in boyfriend also adopted the baby so that there would be two parents (and daddy has baby for the summer by himself - he wanted spend time with the baby, and for Jen to not have to miss out on her summer tradition for one last season). They had to go to county lockdown to get the birth dad to sign off, but it's a done deal - complete with a new first and last name for the baby.
Jen is only 21 but unlike a lot of people would have, she didn't say "oh no, this baby needs to be handed over to the authorities!" She hired a lawyer and dealt with it. She told me that being adopted herself, it never occured to her to do any different.