The seemingly reconciled duo have been working on a duet that Brown is hoping to include on his new album, due out later this year, a studio source tells E! News. "They've been working on it together," the insider says.
We have also learned that award-winning record producer Polow Da Don, who has worked with Brown in the past, has been holed up with them at a Santa Monica recording studio for the past several days.
Reps for Brown and Rihanna have not yet responded to E! News' requests for comment.
In the meantime, while E! had learned that Brown's brief hiatus from music making ended more than a week ago and that he is currently working in Los Angeles on this upcoming album, Rihanna's readiness to record again had remained up in the air until this weekend.
Producer Adonis Shropshire said that the 21-year-old Grammy winner was also back in the studio.
"You have to remember, she's a kid still," he said. "So with anybody who goes through something in the world, you have to bring yourself out of it...I guess her refuge is her music."
Rihanna canceled a few performances in Asia in the week following Brown's Feb. 8 arrest for allegedly attacking her and has yet to make any (intentional) public appearances since.
(Originally published March 10, 2009, at 10:15 a.m. PT.)