When I was a sophomore (14-15), one girl who had previously dropped out of 8th and 9th grade when she got pregnant the first two times, was going to drop out again for her third. That's right, a 15 year old girl having to drop out a third and final time because she was pregnant again. FWIW, apparently they were all by the same guy at least, a doper guy 3 years older with significant mental/anger issues
While that was the extreme case of my small town high school class of about 50, she was only one of about 8-10 girls in my class who had 1 or more before 18. I don't really keep up with any of them anymore, but there only one that is doing anything with her life as far as I know. She has two by the same guy who she's now married to. Also, she went to vocational school her last 2 years in HS while raising her kids and now she's a nurse, and presumably doing fairly well
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Also, my 55 y/o uncle has been a step great grandpa for a few years. His wife is 62 and had kids early from her first marriage. She has a daughter about 47 I think, with 5 kids from 12-34. her oldest has an 18 year old with a couple of kids now. They have like 15 grandkids and 2 or 3 greats. I don't believe any of them are married, and I know most if not all of them are on welfare/foodstamps