Charlize Theron's little boy is growing up fast.
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The actress, who adopted her son Jackson in 2012, said that he's already showing that he has a strong personality.
"Seth [McFarlane] calls him 'the little Republican' because he's just always saying no," Theron told Ellen DeGeneres. "He's a little slow on the speech but he's hitting the 'no' really well."
Theron and McFarlance co-star in the new movie "A Million Ways to Die in the West."
Theron, 38, who has been dating Sean Penn for a number of months, added that she "scored big time" with Jackson, who has been loving seeing his mom on movie posters around L.A. However, he's much more impressed by her co-star, Amanda Seyfried.
"I was driving him to kindergarten two days ago and [he was] ... pointing at the posters and then there was one of all four of us and we were at a light and he said, 'Mama wears cowboy hat!' I went, 'Wow! That's a big -- that's great!'" she said. "Then as I looked back, he's got this big grin on his face and he just goes, 'Other lady princess.'"
"He thought Amanda was a princess and his mom just wore a cowboy hat," she continued. "That was it."