Jamie Lynn Spears’ fiancé Casey Aldridge is reportedly getting advice from Kevin Federline, the ex-husband of Jamie Lynn’s older sister Britney Spears. Aldridge is set to marry 17-year-old Spears, who is 5 months pregnant with their child.

Sources say Aldridge, 18, has asked Federline for advice on he and Spears’ finances. The insider claims that Aldridge is mad at his soon-to-be mother in law Lynne Spears after she attempted to cut him out of a million dollar deal for the first baby pictures of his unborn child.

“Kevin told Casey that he should be involved in every deal that Lynn makes,” says the insider. “Casey knows that Lynne wants her 20 percent cut as Jamie Lynn’s manager, but she doesn’t want to give him anything.”

“Casey thought the money from pictures and interviews would go for Jamie Lynn, the baby and him, but he hasn’t seen a dime. He wants to know where all the money – and all the future money – will go. And he thinks the only way to do that is to marry Jamie Lynn,” the source added.

Meanwhile, the young couple has been house hunting. Sources claim Spears has made a $300,000 offer on a new home.