"Someone suggested that it might only have been a religious Get and
not a divorce in the courts. That would be ok if they parties were
not going to remarry but to remarry as I said they have to prove they
were divorced." [>from Allan Jordan]
There is yet another possibility that I did not consider earlier. It
happened at least once in my family, though later than Marilyn is
researching. My grandfather remarried after my grandmother died, but
for financial reasons (either to keep her public housing apartment or
her Social Security, I think), they had a religious ceremony only and
did not have a civil ceremony. It is possible that this was the case
in the divorce that is being researched. In such a case, depending on
the law that governed common-law marriage at the time, there might
have been only a Get and not a civil divorce.
If they were considered to be married in civil law, then they would
need a divorce to marry again.