Shar Jackson Defends Kevin Federline's Weight Gain

K-Fed ... or overfed?

New uncle Kevin Federline appeared to have packed on the pounds after hitting a Los Angeles golf course Friday. But his ex Shar Jackson says his fuller figure is the result of being a full-time Mr. Mom.

"It's daddy weight!" she tells "When you are a full time parent, sometimes you can't focus on you. If gaining a few pounds is your only problem, life's not too bad!"

Adds his rep, "He's a stay-at-home dad, and people tend to gain weight when they are home with the kids. He's very happy with the way he looks."

Federline was awarded sole custody of Sean Preston, 2, and Jayden James, 17 months, in January. He told Details last year that he has fully embraced fatherhood.

"To be a father is ... everything," the rapper -- No. 7 on Details' Top 50 Power Players -- said. "It shows me how little I am."

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