The actress, 29, is expecting her first child with fiancé David Olsen and is due to give birth this winter, Ruah confirms to PEOPLE.
“I’m so thrilled about having a baby boy and starting a new chapter as a parent with David,” she tells PEOPLE.
“Its amazing how in love I am with this little person I’ve only seen on a black and white screen. I’m starting my own family and there is no other feeling like it.”
If Ruah’s fiancé’s name sounds familiar, it’s because Olsen, 37, is the older brother to fellow NCIS: Los Angeles star Eric Christian Olsen, who welcomed son Wyatt Oliver last month with his wife, actress Sarah Wright.
Ruah and Olsen met on NCIS: Los Angeles where she plays Special Agent Kensi Blye. Olsen, a former Navy SEAL, plays brother Eric’s stunt double on the CBS drama, which kicks off its fifth season on Sept. 24.