David Arquette and girlfriend Christina McLarty are expecting their first child together! Credit: Steven Lawton/FilmMagic

Congratulations are in order for David Arquette and his girlfriend Christina McLarty. A source close to the couple confirms to Us that Courteney Cox's ex and his on-again-off-again girlfriend McLarty are expecting their first child together. (TMZ was first to break the story.) 

The source says they were trying to keep this private, but "it came as a surprise. They are excited and happy even though this was unexpected."

The Scream 4 actor, 42, already has 9-year-old daughter Coco with ex-wife Cox, 49, and this will be the actor's second child. TMZ reports that Entertainment Tonight correspondent McLarty is currently in her fourth month of pregnancy. 

In late October 2013, McLarty exclusively clarified to Us that she and Arquette were not engaged after multiple rumors surfaced. 

"We are totally happy and together in love, but we are not engaged," she said. "It's just a rumor that got out of control." 

Arquette and Cox were married in 1999, announced their separation in October 2010 and finalized their divorce in May 2013. In January 2011, Arquette checked into rehab for alcohol and "other issues." Though he claimed to be sober for more than 100 days on The Tonight Show With Jay Leno in April 2011, it seems he has since fallen off the wagon after calling into the Howard Stern Show and declaring he was "wasted" on Oct. 30, 2013. 

On Oct. 1, 2013, Arquette appeared on Watch What Happens Live and declared that McClarty -- not Cox -- was the "love of my life."