Malcolm in the Middle's Frankie Muniz makes heartbreaking confession about his time as a child actor

Malcolm in the Middle's Frankie Muniz has opened up about his time as a child actor.

He starred on the hit sitcom, which was successful enough to make him a multi-millionaire before his 20th birthday.

Frankie, now 38, was just 11 years old when he first began acting on the show, which also starred Breaking Bad's Bryan Cranston.

By the time he turned 19 eight years later, he was worth $40 million.

Following the success of Malcolm in the Middle, he also starred in Disney's Agent Cody Banks, Racing Stripes and My Dog Skip, as well as guest appearances on Lizzie McGuire and Sabrina The Teenage Witch.

But the move to Los Angeles to pursue the acting dream may have had an unforeseen impact for him and his family.

Speaking on the latest episode of I'm a Celeb Australia, he opened up to his fellow campmates about his experience as a young actor.

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According to Muniz, the move to LA from his childhood home in North Carolina meant that his mom moved out with him, leading to the family being separated.

He said: "Me and my mom went, but my sister stayed with my dad in North Carolina.

"But my mom and dad ended up getting a divorce during that time.

"So in that sense it's kind of sad to think about that it really did separate the family."

The actor added: "I don't know how much positive it brought to the family. I wasn't a part of the family since I was 11 because that's when I left."

Even at the age of 17 in 2003, he had doubts about his future in acting, saying to CBS at the time: "I still don't know if I want to be an actor. I still don't know if that's what I want to do when I grow up."

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He added: "I always said when I got to my first million, we shouldn't be talking about money, but when I got to my first million, I was rich.

“I'm waiting for a hundred, and then I'll be done … because that’s enough.”

Frankie has now left acting for an extremely different career as a NASCAR driver and he is hoping to make it to the top of the game in NASCAR.

Speaking to CNBC's series Make It in 2024, he explained that he'd had wanted to 'take advantage of having the opportunity to do things' as he felt he was 'running out of time'.

He said: "There's a lot of things in my life I've wanted to try. And I've wanted to see if I could find success in these businesses.

"And fortunately, because of what I got as a child actor, it gave me the opportunity to step back and try those other things. It gave me the freedom to do that.

"And I'm forever grateful for that."