03/14/2011 at 03:00 PM EDT
Mel Gibson has a reason to smile.
Following Friday's conclusion
to a long-running court battle with ex-girlfriend Oksana Grigorieva, the Beaver
actor spent the weekend celebrating the birth of his third grandchild.
"He was overwhelmed with emotion," a pal of Gibson, 55, tells PEOPLE of his daughter Hannah's baby boy. "He gets that way around babies. ... He was overjoyed."
Family bonding being a theme, Gibson also spent a portion of the weekend with his and Grigorieva's daughter Lucia, 1.
"He always has a great time with her," the pal says.