Information in this article applies toThe Sims 3for all platforms, including PS3, Windows, andmacOS.
There’s also aresurrection cheat for The Sims 4.
The opportunity is more likely to appear if you clear your Sims' opportunities lists.

Electronic Arts
You’ll receive a call from the lab.
Take the departed’s urn (or tombstone) to the lab.
Choose to resurrect your Sim as a ghost.
Don’t throw away the departed Sim’s urn or tombstone.
If you throw it away, they will forever be stuck as ghosts and become unplayable.
Your Sim is brought back to life and returns home.
If a Sim dies and you didn’t want it to happen, quickly exit the game without saving.
The Sim will still be alive when you restart.
opt for chess table that appears to start the game.
Use a Sim with Gardening skills level 7 or higher.
Catch a Death Fish.
Use a Sim with Fishing skills level 8 or higher.
With the ingredients in your inventory, opt for stove to make the Ambrosia.
Use a Sim with level 10 Cooking skills.