Teen mom Farrah Abraham, 24, is expending the family -- she announced she's adopting a child so her 6-year-old daughter Sophia will have a sibling!

"I’m happy to confirm I'm moving forward in my adoption process. This means I will be making some changes in my career to welcome a new addition to my family. Very excited and this feels so right. I'm very blessed for this opportunity," Backdoor told Us Weekly.

The single mom, who's already starred in a top-selling porn film, Backdoor Teen Mom, told OK magazine, it's the right time for her daughter to welcome a brother or sister: "Sophia is in the right frame of mind and is very supportive as well. She is very open and accepting to understanding that someone else had other parents, and we would be their second parent and be a loving family to them."

Sofia's father died in a car accident in 2009, two months before the little girl was born.