Ok, here is what you need to know and do:
Ok, you probably know that tamagotchis leave their babies 2 days after the babies are born, right? Well, after it has the baby, DO NOT pause it at all and let it sleep the first night and then, the next day, set the time to 11:59pm and wait one minute. The parent should wake up and be looking at it's baby. A few minutes after that it should fly up to the sky. I may not work the first time, just keep trying and it'll eventually work.
Hope I helped!
*~Tamagotchi~*