04/27/2012 04:51 pm ET

LeAnn Rimes, Eddie Cibrian: Co-Parenting Has Its 'Challenges'

LeAnn Rimes, who celebrated her one-year anniversary with husband Eddie Cibrian Sunday, is opening up about the challenges of co-parenting.

The self-described "bonus mom" to Mason, 8, and Jake, 5 -- Cibrian's sons with ex-wife Brandi Glanville -- told "Extra" recently that the past three years have been a "whirlwind."

"Acclimating to having these two little boys in my life and figuring our way around that whole world of you know, co-parenting and kids -- it's been amazing with him and we have a great life, but it's definitely had its challenges," the 29-year-old singer told "Extra's" Terri Seymour, as Cibrian stood by. "We've met them, I think, with grace -- I think it's brought us closer together."

Rimes and Cibrian met on the set of the 2009 television movie "Northern Lights." Rimes and her ex-husband, Dean Sheremet, divorced in December 2009, three months after Cibrian split from Glanville, his wife of eight years. In April 2011, the former co-stars tied the knot.

Despite reports of strained relations between Rimes and Glanville, the pair have reportedly come together at a number of recent family events, including five-year-old Jake's soccer game, where the twosome shared a seat and were photographed laughing with one another.