A source revealed to People magazine that the Gangster Squad actor has plans to adopt Theron's son, Jackson, age 3.
"Charlize and Sean are very serious," a source close to Theron reportedly told People. "Charlize says this is it. Jackson already calls Sean daddy."
"This is the first step toward them getting married," the source adds.
The South African-born actress and Penn have been dating for over a year (since taking their longtime friendship to the next level), and are even rumored to have gotten engaged while on a trip to Paris, France.
Adopting Jackson (who Theron adopted herself in early 2012, when he was 4 months old) would make the tiny tot Penn's third child, as he shares two children, daughter Dylan and son Hopper, from his previous marriage with wife Robin Wright — and Penn might not stop at three kids.
According to Us Weekly, the Oscar-winning stars have big plans for their relationship and they are already talking about more kids.
A source revealed to the mag that "Sean always knew that to truly earn a place in Charlize's heart, connecting with Jackson was one of the most important parts."
The source added, "There is still talk of adopting again and giving Jackson a brother or a sister."
We're glad to hear that things are going so well between this A-lister couple.
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