Chris Masterson and Yolanda Pecoraro are expecting their first child together.
Yolanda Pecoraro (c) Instagram
The 40-year-old actor and Yolanda have announced the news via social media, with the expectant mother sharing a picture of her growing baby bump on Instagram.
Yolanda - who married the actor last year - captioned the post: "Baby Masterson."
Chris' sister Alanna commented on the post, expressing her delight at the news.
She simply replied: "Baby baby baby!!!! (sic)"
Georgie Flores - who starred in the TV drama series 'Famous in Love' - was similarly thrilled by the announcement.
She said: "There aren’t enough hearts to express my excitement!!!! But here’s a few anyways [love-heart emojis] (sic)"
Chris is best known for playing the role of Francis in 'Malcolm in the Middle', and his announcement arrived shortly after Frankie Muniz, his former co-star, revealed he's expecting his first child with Paige Price.
In September, the actor confirmed the news in a YouTube video, revealing their baby is due to arrive in March 2021.
He said at the time: "In the past four-and-a-half years, Paige and I have experienced so many incredible things together. We've travelled the world, got to live out all these once-in-a-lifetime opportunities.
"While we still believe it's the little moments in between the big ones that make you feel happiest, nothing quite compares to hearing your little one's heartbeat."
Frankie, 34, admitted he already can't wait for the arrival of their baby.
He continued: "We felt like we were living and experiencing a real-life miracle for the first time. The second I heard that heartbeat, reality set in.
"I was throwing out baby names and future career choices."
Paige added: "When we found out that we were expecting, we were both in a state of disbelief. We knew that we wanted this, but were told our chances wouldn't be that great … We beat the odds."