I would never recommend that minors have children. However, I know a few people who had mothers that were underage when they were born. To my surprise, they each had a great childhood. These people are exceptional and well-adjusted. They were fortunate to have good mothers and extended family to help.
Personally, I was born in the more traditional way, but my father took off when I was eight. I was also fortunate to have a good mother and grandparents. I've done ok too, but perhaps with a few more scars than the others I speak of.
Life is a great journey, but the hard part is getting started. I'm glad that the random decisions my mother made, led to my existence, and so is my Mom. Hopefully, this new child, and his mother will feel the same, when he is grown.