"I spend most of the day chasing my kids around the house," he tells In Touch Weekly magazine. "Their needs define my schedule every day."
Federline has had sole custody of Sean Preston, 2, and Jayden James, 18 months, since early this year after months of bizarre behavior by his ex-wife, Britney Spears. The couple, who wed in October 2004, divorced last July.
"It is so very important to me that my children will always know and never question, that no matter what happens, they have a mommy and daddy who love them very much," Federline, 30, tells the magazine.
Federline also has a son and daughter with ex-girlfriend Shar Jackson.
"I will always love the mothers of my children, and I will always be there for both of them," Federline says.
"I believe that any good energy I put out there brings more good energy into my own life. The relationships with my kids and family will last my whole life and are the most important to me," he says.