I did that numerous times, not counted but very much times with the same couple or different ones, but after I tried again now, ironically it made a baby.

Yes, I am at the start of the game, only 2 technology branches updated and only 1 puzzle solved, currently building up the "[censored]" dam (witch of course takes a lot of more time than when bulding or repairing huts.

Thank-you for your help laurence