Adoption

Adoption is an option in both The Sims and The Sims 2. It allows a couple to adopt a child. One person cannot adopt a child.

The Sims
Sims couples get calls from adoption centers randomly asking if they want to adopt a baby. Although sometimes they have to be the same gender

The Sims 2
Sims can adopt a child over the phone if they call Service and then choose "Adoption Center". They could only do this however if the Social Worker had not taken one of their kids. The household must have 3000 simoleons to adopt.

If you are approved the Social Worker will bring your new child the next day at 10 AM. To make sure someone is there to receive the child, it's best to call the day before a Sim's day off.

At 10 AM the Social Worker will arrive and a screen will pop-up asking you if you wish to adopt a baby, child, or toddler. This is the only option you have when adopting.

It is possible to get a kid that was taken away by the social worker in another family.