Color me a bitch *shrug* (I believe abortion is a moral issue, and my morals are shaped by my spiritual beliefs). I had a baby at 19 and was married and still was a stressed out mess most of the time, my son's early life shaped by decisions made by necessity versus picking the best option. I had no education, no job skills and was a stay at home mom because I couldn't get a job that would leave profit after the cost of daycare (our parents worked). I love my son, and thank the gods his head is relatively screwed on but it's sheer dumb luck, not skill on my part. He would have done better being born under better circumstances to more mature, better positioned people. Maybe the O/P is financially well to do and will be able to help her out and everything will work out, but no matter what, if his daughter has the baby and keeps it everything for the next 18 years is going to be shaped by one action made by a couple of dumbass kids with crappy judgement.
Bear in mind, I myself was the daughter of a single mother who was not married to my father (who was a psychotic bully). While she was older than the O/P's daughter, she eventually had to quit working due to an inability to find safe, reliable child care (at least two of the babysitter's were flat out cruel to me when I was a young toddler). I grew up on welfare. Determined not to repeat my mother's mistakes I went on to marry too young (because I was afraid of being single for the rest of my life) to a man who was an abusive asshole (not terribly different from my own father) and have a child way before I was ready. History repeats itself ad infinitum.