The Hacksaw Ridge director was discussing his latest film -- in theaters on Nov. 4 -- with Michael Strahan on Tuesday's Good Morning America, where he couldn't help but quip about expecting another baby.
"I've got the stretch marks, man," the 60-year-old actor joked. "I've got stretch marks!"
"That happens after you get past five," Strahan responded.
This will be Gibson's first child with his girlfriend of two years, Rosalind Ross.
Gibson discussed his upcoming ninth turn at fatherhood with ET last week at the Hacksaw Ridge premiere, admitting, "I feel fortunate."
Gibson has six sons (Christian, Milo, Louis, Thomas, Edward and William) and two daughters (Hannah and Lucia), but is keeping the gender of his newest child close to the vest, joking, "You could take a guess and you'd be 50 percent right."
Meanwhile, Gibson, who recently hit 10 years of sobriety, has tried to count his blessings about fatherhood and his return to the director's chair.
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