I had only heard that she got them while working at the bank.
Who knows really. You can get obituaries everyday in the newspaper now? And SSN’s are readily available online through social security death index once the people are deceased.
I remember reading how people took on other identities in those times but I can’t remember how. SSN’s at one time were on personal checks. Probably now with computerized Social security Obama would nothave gotten away with it.