Farrah has always been open about her desire to get married and share life with a special someone -- and Sophia's mama seemed to be making strides in that direction when she went shopping for that bauble with Simon last season on Teen Mom OG. But during this week's premiere episode, the entrepreneur was frustrated because she had made the major engagement ring purchase on her own, and she vented to her mother Debra that her on-again off-again beau had not yet given her the money for the expensive rock.

The big question: Why did Farrah shell out the money for the diamond?

"I bought my own engagement ring thinking that Simon would be paying me back since he said to buy it," she reveals to MTV News in the video below.

A bit more context about the experience: Farrah was in the Bahamas with her mini-me (celebrating the little lady's birthday), and the duo found themselves in a jewelry store.

"She was like, 'You should get an engagement ring,' and so she wanted to help me pick that out," Farrah remembers about the moment with her daughter. From there, Farrah gave Simon a call to ask if he was okay with this idea and to make sure he was involved -- and he even spoke with the owner of the business about how to customize it.

So has Simon given her the cash for the ring since the premiere episode aired? How much did it actually cost? And does she wear it now? Found out in the clip, and share your thoughts about this big purchase in the comments. And be sure to keep watching Farrah every Monday on TMOG at 9/8c only on MTV.