Jennifer Garner and Ben Affleck have named their newborn son Samuel.

The couple - who also have two daughters, six-year-old Violet and three-year-old Seraphina - welcomed their "healthy" third child on Monday in Santa Monica, California.

"We are happy to announce on February 27, Jennifer gave birth to a healthy baby boy, Samuel Garner Affleck," Ben wrote on his Facebook page.

The 39-year-old actress - who has been married to the 39-year-old star since June 2005 - recently revealed the pair's daughters had been thinking of possible Disney-related names to call their newborn child: "Our girls are working on names. At first they were definitely Disney. It was like, Donald Duck, Minnie Mouse Affleck. And then they've moved on. Then it was Peter Pan, Captain Hook, Smee."

Jennifer and Ben announced her pregnancy in August 2011, but the couple were reluctant to divulge details of the child's sex.

The brunette beauty has previously said it would be "weird" to have a boy, but also "cool and different," while she once suggested that Ben wanted to have a son as his third child.

"I would have thought [he wanted a boy]. At first...I really thought so, and then [Ben] kind of said, 'Well, we have girls. We know how to do girls. My girls love me. I'm the big guy in the house.' So, now I'm not sure," Jennifer explained.