Malcolm in the Middle's Justin Berfield shares what he knows about Erik Per Sullivan’s current life

Malcolm in the Middle star Justin Berfield has told fans that Erik Per Sullivan is 'really happy' ahead of the series reboot.

Disney and Hulu's upcoming reboot, Malcolm in the Middle: Life's Still Unfair, of the iconic noughties show is hitting our screens on 10 April, marking two decades since the series finale aired.

The four-part miniseries will catch up with Frankie Muniz's Malcolm as he prepares to celebrate his parents', Hal and Lois, 40th anniversary.

Alongside Muniz, the series will also see familiar faces such as Bryan Cranston, Jane Kaczmarek and Christopher Masterson back in their roles alongside a slew of new faces.

However, there is one person who will be noticeably absent from the reboot, Dewey actor Erik Per Sullivan.

34-year-old Sullivan's last acting credit came in 2010, in teen crime drama Twelve, with the former actor now living a life outside of Hollywood.

What is Erik Per Sullivan up to now?

Sullivan's former castmates have given numerous glimpses into his life, with Reese actor Justin Berfield revealing during an interview on The Joe Vulpis Podcast that Sullivan is 'really happy' with his life.

"I talked to him, I think it was after my daughter was born," Berfield, who shares two children with wife Liza Almeida, explained, adding: "We emailed back and forth."

"He was checking in, and I think his parents emailed me, too."

Berfield went on to explain that even though he and Sullivan don't talk 'too often', he knows his former co-star is doing 'really well' at the moment.

"He's happy, Berfield continued. "He's a good guy. He's like, really happy though."

Erik Per Sullivan (far right) is the only actor not returning for the reboot (Fox)

Berfield confirmed that Sullivan was initially offered his role as Dewey for the reboot but declined, with the part ultimately being recast and Caleb Ellsworth-Clark taking over.

"I know they asked him to be a part of the show, and he was just like, 'No, I'm done. I'm done with that part of my life'," he added.

Berfield isn't the only Malcolm in the Middle star to share insights into where Sullivan is now, with his TV mother and father also sharing tidbits with fans.

In an interview with PEOPLE, Kaczmarek revealed that Sullivan is currently studying for a Master's degree in Victorian literature, telling the outlet: "I admire it too because so many people think being in show business is the greatest thing in the world. It's not for everyone."

Meanwhile, Breaking Bad star Cranston told Entertainment Weekly that his on-screen son was 'really smart' and studying at Harvard.

However Justin Berfield has confirmed his former co-star is 'really happy' (Michael Tullberg/Getty Images)

Revealing that Sullivan was also supportive of the reboot, he said: "I talked to Erik, and I said, 'Hey, we got the show! It's going to come back.' He goes, 'Oh, that's fantastic!' And I go, 'Yeah, so we're looking forward to having you back.' He goes, 'Oh, no, no, I don't want to do it. But it's fantastic'."