By Amber Goodhand - Radar Reporter
The 39-year-old Good Will Hunting star announced the name Wednesday morning on his official Facebook page.
"We are happy to announce on February 27, Jennifer gave birth to a healthy baby boy, Samuel Garner Affleck," Ben wrote.
Jennifer, 39, gave birth to Samuel on Monday -- making Violet Anne, 6, and Seraphine Rose, 3, big sisters.
Ben and Jen were married in 2005 in a private ceremony while Jen was already three months pregnant with their first child.
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