The Sims 3
50 Achievements
1,000
30-35h
Once a Parent, Always a Parent
Welcomed a child into the family.
40
How to unlock the Once a Parent, Always a Parent achievement in The Sims 3 - Definitive Guide
Easy!
So heres how to get it easily as a male sim:
1. Meet a female and start flirting; make sure she's single because it takes more time and effort to have a married sim cheat.
2. Go to your home and repeat the flirting process until it says she finds you extremely irresistible.
3. Try for baby with her and listen for the jingle; if you hear it she's pregnant if not then try for baby once more.
4. Go about your business and a few sim days later you'll get the achievement.
You get the achievement without having to take care of a baby which could be helpful if you are working on other achievements as well.
Once you've WooHooed for the first time (See Woo Hoo! on how to) another option will come up called "attempt a baby." Keep hitting that option until the game tells you that the woman is pregnant. The baby takes about 7-10 in-game days to be born so until then just wait it out. The woman will eventually need to go to the hospital to have the baby. Once you get to the hospital you've got to wait a couple in-game hours for the baby to be delivered. Your family will walk out of the hospital and soon after the trophy will pop.
To have a baby you have to do the same thing as making "Woo Hoo" but instead of picking the "Woo Hoo" option choose the "Try for baby" option. You will not get told that the Sim is pregnant until after a few days. The pregnant Sim will get home pay and have a child in a few days. Aging doesn't affect this achievement and you can leave it off.