By Jake Perlman
October 29, 2013 at 11:21 PM EDT

NCIS star Michael Weatherly, 45, and wife Bojana Jankovic, 32, welcomed their second child today, a boy named Liam. The actor enthusiastically tweeted news of the arrival, just 18 months after the couple’s first child, daughter Olivia, was born.

Weatherly, who plays Special Agent Anthony DiNozzo on the CBS series, is also father to 17-year-old son August from his previous marriage to actress Amelia Heinle. Weatherly was also previously engaged to his Dark Angel co-star Jessica Alba from 2001 to 2003. Weatherly and Jankovic were married in 2009.