If Jamie Lynn Spears knows what’s good for her, she’ll run, not walk, away from big sister Brit’s latest Olive Branch extension. Guilty after pressuring her teen sister to place her unborn baby up for adoption and rumored to be secretly pining for a baby daughter of her own, child hostage holder Britney Spears wants Jamie Lynn and the baby to move in with her.

“Britney is trying to convince Jamie Lynn that they would have a blast,” says a Star Magazine source. “They could be together all the time, just like they once were. Jamie Lynn is so scared and confused right now, she’s actually considering it.”

Brit hopes she’ll be able to keep supposed father Casey Aldridge out of the child’s life:

“Britney doesn’t like Casey. She calls him a dim-witted pretty boy.”

“Britney knows she has not been the best role model lately. She didn’t look out for Jamie Lynn enough and failed as a big sister. All she can do now is put the offer out there and see what happens.”

But the Star Mag insider, along with the rest of the free world, believes Britney Spears in the proximity of another child will spell disaster:

“Jamie Lynn is not mature enough to understand what being around Britney 24/7 could do to her baby.”