If you want to turn a Ghost Sim back into a Human (Death By Old Age) in The Sims 4, then this guide will help you to do so.
1. If any of your sims died due to Old Age, you can get them back from Ghost to human. You have to press CTRL+Shift+C altogether and hit enter on your keyboard to open the cheat box.
2. A white box will appear at the top left corner of the screen. Type in “testingcheats true” and hit enter to enable the cheats.
3. After that, input “traits.remove_trait ghost_oldage” and hit Enter on your keyboard. Press CTRL+Shift+C again to hide the cheat box.
4. You will see your sim gets back to life.