The two, who were first spotted together in December, have hit the recording studio together.
Kerry Brown, a producer, posted pics of Jessica and Billy working on music on Twitter. And in response to one of the Tweets, Jessica wrote of Billy, "He braids my prayers."
Jessica seemed to be enjoing herself in the studio, Tweeting, "Fun to be lost in laughter" and later, "I am blessed."
A source told E! News late last year that Jessica is gaga over the Chicago rocker.
"She has fallen hard and is smitten," a source told the Web site.
Billy, 42, who previously has been linked romantically with Courtney Love and Tila Tequila, may reportedly be making Jessica happy, but another source told E! at the time that he hasn't fit in with the family yet.
"He's just another in an endless string of Jessica's boyfriends," the source said. "They think he's too old for her. No one takes any of her boyfriends seriously anymore because she has had so many. They're sick of all of them being 'the one.'"
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