Their first, daughter Sam Sheen (search), was born in March.
"They are incredibly thrilled and I couldn't think of a better Christmas present for the both of them and for little Sam," the magazine quotes Richards' agent, Chuck James.
Richards, 33, and Sheen, 39, married in June 2002. The couple met while shooting the film "Good Advice" in 2000. They began dating after Richards did guest spots on Sheen's former TV series, "Spin City."
Sheen also has a daughter, Cassandra, 20, from his first marriage.
He now stars in the CBS sitcom "Two and a Half Men," (search) for which he received a Golden Globe nomination for best actor in a TV musical or comedy earlier this week.