There is two rules to this challenge: No Mutation menu! (This also means no console!) Babies can only be born when it is raining. If you are on an island where it snows instead, that works too. This seems very simple. IT IS NOT. What my tribe went through: Started a new save on Grass Adventure. It soon rained, and my female had identical twin boys. It rained again, and I managed to fit in two baby boys before it stopped.  My starters passed away,