Gibson has seven children with his former wife, Robyn Moore.
He also has a 6-year-old daughter with ex-girlfriend Oksana Grigorieva. Now, he and his current girlfriend, Rosalind Ross, are expecting another child.
A close friend of the couple told People, "Mel loves being a dad and he and Rose can't wait to be parents together. The last two years have been some of his happiest years he's ever had."
Find out more about Gibson's brood of children below.
Hannah is Mel's first child with Moore.
She married blues singer Kenny Wayne Shepherd in 2006 and now has three children of her own — Mel's only grandkids to date.
Christian, along with twin brother Edward, was born in Australia in 1982.
Though Christian hasn't pursued acting, he did have a minor role in the 2002 movie We Were Soldiers.
Christian has had some run-ins with the law, like his father. In 2005, while studying at the University of Colorado, Christian was arrested for a DUI.
He is also a landscape photographer and told the Malibu Times that he's inspired by Australian photographer Ken Duncan.
Edward, Christian's twin, has also had some struggles like his father's. In 2007, he entered rehab to help him recover from alcohol and cocaine addictions, according to the Enquirer.
Now, Edward seems to be on a great track, though. He makes furniture out of reclaimed wood from Fiji.
He's also into motocross.
William had his share of trouble, too. He was reportedly kicked out of school for a weed-related offense back in the day.
But the Gibson boys aren't all bad, despite their run-ins with the law. A neighbor described the kids as "a rowdy bunch, but also nice — very 'Yes, sir, no sir,' which you don't get a lot of around here."
Louis seems to be the Gibson kid who is most out of the spotlight. There is very little information that we could find about him online, aside from his age.
According to the Daily Beast, Milo is the closest to his father of all the kids.
Milo's IMDB bio says that he "trained and worked as an electrician in Malibu for a number of years before following his dream." He is now studying drama in Santa Monica.
Milo will have a key supporting role opposite Jennifer Garner in the upcoming film The Tribes of Palos Verdes, according to The Wrap.
People reported that Robyn Moore filed for divorce from Mel just a day after Thomas turned 10, though the family apparently worked hard to protect him (and the other children) from the "confusion and increased scrutiny" on the family.
Lucia is the only child Gibson had with ex-girlfriend Oksana Grigorieva.
Despite the custody drama, Mel has maintained a relationship with his daughter.
Gibson and girlfriend Rosalind Ross have been dating for two years and are currently expecting their first child together. The baby is expected to be born at the beginning of next year. Ross is a writer and a former champion equestrian vaulter. This will be her first child.
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