He is most likely not Ruth's husband.
Card shows wife as
Cora.
Are you looking for a Robert just because of Robert's name or have you found some definitive information?
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Since Robert Jr. appears in the 1920 census as having been born in Mass. around May-June 1916, I would suspect that the mystery
Eldridge was still in Mass. for the draft registration, if still alive.
Searching for any
Eldridge in Middlesex and
Suffolk Counties turned up nothing.
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