How did that work out for him? It seems I recall it was a marriage of convince and Einstein got out of it by promising to give her the Nobel Prize winnings to her. Anyway, it does seem unnatural for a woman to bed a close relative....you agree with that, i am sure.
The first wife got the nobel prize winnings. The second wife was his cousin and they were together till he died.
The second marriage was about convenience but they did have 2 sons together. He was not comfortable in crowds and she enjoyed it so it seems to have worked.