Just as one might expect twins to fancy similar people, so one might expect their partners to feel a parallel attraction: that anyone who fancied one twin might also be expected to fancy the other. Again, Professor Lykken has found this not to be true.

Does twins come from Mom or Dad?

For a given pregnancy, the odds of conceiving fraternal twins are only determined by the mothers genetics, not the fathers. Fraternal twins happen when two eggs are simultaneously fertilised instead of just one.