Mel Gibson welcomes ninth child, first with girlfriend Rosalind Ross

Mel Gibson just became a new father for the ninth time.

The Hacksaw Ridge director and his girlfriend of two years, Rosalind Ross, have welcomed their first child together, Gibson’s rep confirmed to ET.

The couple’s new son, Lars Gerard Gibson, was born in Los Angeles on Friday, weighing 5 pounds, 5 ounces.

WATCH: Mel Gibson opens up about expecting his ninth child at ‘Hacksaw Ridge’ premiere

Gibson is already the father of eight children. The Oscar-winning filmmaker shares seven children with his first wife, Robyn Moore, including one daughter — Hannah, 36 — and six sons — twins Edward and Christian, 34, William, 31, Louis, 28, Milo, 26, and Thomas, 17.

Gibson and Moore separated in 2006 and their divorce was finalized in 2011.

Gibson also shares a 7-year-old daughter, Lucia, with his ex-girlfriend, Russian singer-songwriter Oksana Grigorieva.

WATCH: Mel Gibson talks expecting baby No. 9: ‘I’ve got stretch marks!’

Earlier this month, ET caught up with the Braveheart star at the Golden Globes where he jokingly bragged about having more kids than Clint Eastwood.

“I was talking to Clint the other day. I said, ‘How many kids you got?’” the 61-year-old actor shared. “He said, ‘Eight.’ So I’m beating him.”

Coming soon: a sequel to The Passion of the Christ, but first, Gibson’s latest directing effort, the World War II drama Hacksaw Ridge, debuted earlier last year at the Venice Film Festival to a 10-minute standing ovation. It was released in theatres on Nov. 4.

With files from Chris Jancelewicz & The Associated Press