Chris Brown proposed to his girlfriend Karrueche Tran over the weekend, according to reports. A source close to Tran reportedly told Media Take Out that the singer popped the question - without a ring - to Tran. Brown is currently serving time in a Los Angeles jail for violating his probation.

"According to our insider - who is COMPLETELY CREDIBLE  - Chris and Karrueche's relationship has grown STRONGER THAN EVER since he's been locked up," MTO writes.

Reportedly, the 25-year-old told Tran that once he's released from jail he wants to "marry her." The source claims that the model was ecstatic to hear Brown say that. Earlier today (May 5) Tran posted a sweet message to the "Loyal" singer who is celebrating his birthday behind bars.

Tran Instagrammed a photo of the two with the message, "Happy Birthday Christopher. I love and miss you. Can't wait to give you a big kiss and hug."

MTO isn't the only site reporting on the couple's rumored engagement news. A source told Hollywood Life that Brown has been seriously thinking about marrying Tran because she has stood by his side throughout all his legal trouble.

"I don't know if that's him being lonely in jail but that's what he tells her," the source said. "He calls her his wifey and tells her all the time that she's perfect wife material. He knows Kae is incredibly loyal and has literally put her life on hold to hold him down in jail."

"She's taken care of just about everything in his house," the source added. "He basically told her that when he gets out things are going to be way different between them, and that he's going to return all the favors she's given him with a surprise of a lifetime."