Some members of my family have no record of birth or formal existence until they were quite old. Obligations on parents to generate that paper trail exist now

Some members of my family have no record of birth or formal existence until they were quite old. Obligations on parents to generate that paper trail exist now but there are still many ways people can fall into the cracks. The US has generally been far more accommodating of Americans without documentation out of necessity than I think people realize. Some parents choose this for their children, either intentionally or through negligence, and those children need a way to bootstrap their documentation as adults. There was a large contingent of Americans born outside the US to American parents in the aftermath of WW2 that frequently had little or no documentation.