Livia is one of the playable characters and she is pregnant. She is waiting to give birth. She's also a good cook , like bruno.

All you have to do to get this achievement is to start a game with the character Livia and win the game.

The easiest way to do this is to build a game from the workshop and play with Livia, Katia and Marko in my opinion. While you can cook with Livia, you get a lot of things from trading with katia, and if you loot with marko for a few nights it will be enough.

Choosing Port, Sniper Junction, Looted gas station while choosing a location can be an option to win the mission without ending the war. It will also unlock the Epilogue: Exodus achievement for you.