1. Stock Energy Drink, Multivitamins, Antibacterial hand gel, all fruits (blood orange, sweet mango, perfect bananas).
2. Upon entering the game and find that your people is Lying in Repose, hit the space button immediately to pause the game.
Note that this will only work if the spirit has not left the body and wave at you.
3. Feed the dying person the energy drink first, then all of them items above next. You will be able to move the person around and play him/her again although the rest of the household is still mourning. You will notice that the state of the person will gradually change from Extremely Weak - Weak - A little Weak - Normal [this is when the status stop showing Health and start showing other states (Hyper, Elated, etc)]
4. If the health isn't normal yet, keep the game on pause and recheck back on the stores twice a day (morning and afternoon, usually) to buy the items mentioned above and keep feeding the person those items.
5. After health reaches normal, un-pause the game and play normally.
6. If the person is dying again, repeat everything from step 1.
7. Be patient. I had to resurrect my people 2 times before I got the achievement.