Mel Gibson 'Overjoyed' by Birth of Third Grandchild

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.”

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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.