Have you always wanted your Sims to have twins? If so, then you are in luck! In The Sims 2, there are three ways to do this, rather than waiting for it to happen by itself. The first two methods require The Sims 2: Open For Business and The Sims 2: Free Time add-ons, and the third method is using cheat codes.
Steps

Step 1. First way
This method will work if you have The Sims 2: Free Time or later expansions or item packs installed. PLEASE NOTE: Your Sim's main focus should be "Family", only then will this method work properly.

Step 2. While in real time, go to the "Aspirations" button
This button can be found in the panel of a female Sim who is about to give birth to twins. This tab brings together all of your Sim's aspirations.

Step 3. Go to the third tab at the bottom and click on the picture on the left

Step 4. Press until you reach the "Super Fertility" quality at the top of the panel
This quality will be worth 4 points.

Step 5. Now your couple has a better chance of having twins

Step 6. Second way
Using codes.

Step 7. When your Sim becomes pregnant, open the cheat codes window
To open the cheat codes window, press ctrl + shift + c.

Step 8. Enter the cheat code
In the white text box that appears, enter the forcetwins cheat code.

Step 9. Your Sim is guaranteed to give birth to twins

Step 10. Third way
It will only work if you have The Sims 2: Open For Business extension installed.

Step 11. Have your pregnant Sim eat the cheesecake
So you will have every chance of having twins.
Advice
- There are many rumors about how to have twins in The Sims. The only food that gives birth to twins when using the Open For Business extension is a cheesecake, which must be eaten once during a Sim's pregnancy. The only cheat that works is forcetwins.
- Unlike the sex of the baby, the likelihood that your Sim is expecting twins is determined early in the pregnancy. You won't be able to reload the game and have your Sims expecting one child instead of twins, and vice versa.
- In the first case, you will need the The Sims 2: Free Time extension, which installs the Aspirations panel in the game.