OK! EXCLUSIVE: Britney & Jason — Drama at Home!

Yes, they're back together, but for Britney Spears and her agent boyfriend, Jason Trawick, nothing is ever simple. The latest hurdle? The singer has moved her mother, Lynne, into her Calabasas, Calif. Home, a source tells OK!.

OK! GALLERY: BRITNEY & JASON GET THEIR DAILY DOSE OF THE OUTSIDE WORLD

The decision was made without Jason's knowledge.

OK! GALLERY: BRITNEY TAKES A COFFEE & SMOKE BREAK BEFORE DINNER DATE

"Jason felt like he had absolutely no say," says the source. "But he let it slide because Brit's mood improves by leaps and bounds when her mom is around, and Lynne helps at defusing fights between Brit and her dad."

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