‘Clueless’ Britney Spears had no idea ex Kevin Federline was about to have a baby when they started dating

BRITIE Spears had no idea her new boyfriend had a baby on the way with his ex when they first met.

The 41-year-old singer had no idea about the situation between Kevin Federline, 45, and pregnant Shar Jackson when they met in 2004.

Despite the shock, she married Federline in September of that year, and they had sons Sean Preston in 2005 and Jayden James in 2006.

Baby One More Time star Britney says she felt connected to former dancer with ‘bad boy image’

In her new memoir, The Woman in Me, she says she finally learned about his past from a friend.

She wrote: “I lived in a bubble and didn’t have many good, close friends to confide in for advice.

“I had no idea until we were together for a while and someone said to me, ‘You know he has a new baby, right?’

“I didn’t believe it, but when I asked, he told me it was true.

“He told me he saw them once a month.

“‘Do you have children?’ I said, “Do you have children? Not just one child, but two children?”

“So they did a number for me.”

In the book, out Tuesday, Britney claims their relationship turned sour when he became “fascinated by the fame and power” of being a celebrity.

She filed for divorce in late 2006 and claims her lawyer advised her to act before Federline.

She writes: “I was led to believe that it would be better if I did it first so that I would not be humiliated.”