Wladimir Klitschko, 38, and Hayden Panettiere, 25, delighted fans by celebrating the New Year with an Instagram post of their family on Sunday. Their beautiful newborn daughter, Kaya Evdokia, slept soundly as mom preened for the camera and dad snapped the shot. Klitschko posted the cute picture with the hashtags "#newyear" and "#family."

"[Klitschko] has always wanted to be a dad," Panettiere told People. "I think at some point he might have started thinking he wasn't ever going to be and then he was. He is just so over the moon."

Over the past couple of months, Panettiere revealed pregnancy and childbirth took its toll on her body. The "Nashville" actress told Hello! Magazine in November she gained over 40 pounds during her pregnancy.

"I'm 5 feet, 2 inches and I started out at 106 pounds and guess how much I weight now? Around 145 pounds," she said. "And the worst part is that my feet are still size five, and they're going, 'What's going on with all this weight?' They're about to snap from underneath me with the strain."

The expectant mother also said she was thrilled to have a girl first because "I feel like I know a lot about raising a strong woman. I feel very empowered myself and I think my daughter will, too."

After giving birth to Kaya, Panettiere said childbirth "ruined parts of me" during a December interview with People magazine.

"I'm limping around. I'm still trying to figure out what [pregnancy] has done to my body, how it's changed it. What's temporary and what's permanent," she said.

The petite actress and world heavyweight champion started dating in 2009 but broke up in 2011. Shortly after the break up, Panettiere started dating NFL Jets Player Scotty McKnight. The relationship with McKnight was short-lived as she reconciled with Klitschko who proposed marriage in October 2013. Panettiere became pregnant with Kaya in April 2014.

Klitschko will likely spend every moment he can with his new daughter before traveling to Austria in April. There, the former Olympic boxer will spar with New Zealand heavyweight boxer Joseph Parker at a training camp to prepare for his next title bout.