"Don't worry little girl you can hold on as tight as you want for as long as you want," he captioned this sweet pic. "I'm already yours and I'll never let go. I've now [got] two incredible women in my life. My son and I are two lucky guys."
A name for the baby or details about her birth have not yet revealed. Murray and Roemer welcomed a baby boy on May 31, 2015, though his name has also not yet been shared publicly.
The 35-year-old actor, who cemented his WB crush status with roles on Gilmore Girls and Dawson's Creek, is currently playing music icon Sam Phillips on CMT's new series Sun Records, which premiered last month. He's also had recent stints on Scream Queens and the now-canceled Agent Carter.
Roemer has starred in TV drama The Event as well as films like Disturbia, Asylum, Hachi: A Dog's Tale, and The Grudge 2. The 32-year-old actress' most recent role was the female lead in the 2016 vampire thriller Manhattan Undying opposite Luke Grimes.