Christmas will be extra special for Charlie Day this year - he's expecting his first child in December.

Day's actress wife Mary Elizabeth Ellis, his co-star on TV sitcom It's Always Sunny in Philadelphia, is five months pregnant with the couple's child.

He tells People.com, "We've got a kid due in December. We're five months along, and she's feeling great. We're excited... We decided now is the time, and we were fortunate that it happened."

And the Horrible Bosses star is grateful the baby is due in winter because the parents-to-be will be on a shooting hiatus.

He adds, "It's going to time out perfectly. We live in L.A., (so) my East Coast family and her Southern family may have to come see us this Christmas."

The couple married in 2006.