My rabid Christian fascist in denial libertarian co-worker preaches all day about Marx being a Demon worshiper who cheats on his wife willy-nilly and cites that dubious claim as historical facts.

I personally think it’s more likely Engel’s kid, not the child of someone else outside of Marx’s household alltogether since all historical evidence that surrounds the man points towards him being a serial monogamous wife-guy with a bad case of loving his wife a huge amount.