This guide is for people who don't want to have to buy the City Life expansion pack.
Ok, the 'Triple Play' trophy is the hardest trophy in the game, and is basically luck based. you could get this at the first attempt, or it may take you 100 hours. I finally figured a way to have 7 chances for triplets per attempt, and one attempt every 15-25 minutes (Depending on how fast you are). It does take a bit of time setting up, but I highly recommend doing it.
Here is a step by step guild on how I got the trophy in the end.
Step One - New game and create a new household.
Step Two - Have the new household consist of one adult male & seven adult female.
Step three - Have all 8 sims have Family Aspiration.
Step Four - Have all 8 sims have these traits, Family-oriented, Romantic and finally Bookworm.
Step Five - This is important. Make sure all 8 sims have a different surname to each other.
Step Six - Start game with new household
Step Seven - Once game has loaded, go into build mode and add home traits located in top left corner of screen. Have your home have these traits Homey, Natural Light & Teen Neighborhood. (Not sure if this helps, so might be able to skip this, but this is what I had done)
Step Eight - Use the cheat to give all 8 sims the Fertile trait. This cheat will NOT
disable achievements. To add the fertile trait to each sim you have to do one sim at a time. To activate the cheat -
1) Have the sim you wish to give fertile trait selected.
2) Press and hold L1, R1, L2 & R2. This will bring a command bar up on the top of your screen.
3) Highlight command bar and press X. Now enter this code Traits.equip_trait Fertile
4) Repeat previous steps for all 8 sims, and check all 8 sims have the fertile trait.
Step Nine - Build relationships with the 7 female sims using your male sim. Now your object here is to get all 7 sims to the point they will try for a baby with you. I recommend building relationship's with one sim at a time. So basically do this -
Preparing female sims.
1) Build friendship up, I like to get the friendship green bar to around 40-50% full before romancing starts..
2) Start romancing until you have the option to try for a baby but don't try for baby just yet. Do not ask any sim to be your girl friend or get married in this step. Depending on how fast you are at getting through all sims, I recommend building your romance up alittle, as over time your romance bar drops while working on other sims.
3) This step is optional.
I did this step as my sim was living in a small house, and at times things can be a little hectic, and my sims would get jealous of each other when I romance with them. Move the newly romanced female sim out of household into their own household using the manage world/household (located top right of screen) or press start and select manage worlds. For more information on how to, check this link out - http://www.carls-sims-4-guide.com/tutorials/moving-sims.php
4) Repeat previous steps with the remaining 6 female sims. Just make sure each female is in a household on their own, if you chose to do step 3. Don't stick all 7 female sims in the same household as there wont be room for future babies.
Step Ten - Now you should be at the point where your male sim is living alone and the 7 female sims are living by their self's. Wait until 7am or just before and make a save.
We will call this save one, and Do not overwrite this save at any time or you will have to start again from beginning.
Step 11 . That's all the Preparation done, so now Lets begin making babies!
1) invite one of the female sims to your home using the mobile phone.
2) Once sim arrives, try for baby.
3) Then ask her to leave.
4) Repeat with all 7 female sims.
5) Make a new save.
We will call this save two.
6) Fast forward 2-3 days until all seven females have had children. To know when the babies have arrived, some (Not all) sims will ring you to inform you are a dad. You can keep our eye on the relationship tab located bottom right of screen for when the babies are born.
7) If none of the females have triplets, reload save one and repeat all of step 11 from the beginning, and so on until you get triplets.
8) When one of the females gives birth to triplets, make a note of which female it was and reload save 2 and invite her round to your home using the mobile and ask her to move in so she is a controllable sim.
9) Now just fast forward until she has those triplets and you get your achievement.