Frankie Muniz and his wife Paige Price are expecting their first child together

Frankie - who married Paige in February - said: "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."

The actor - who played the title character in 'Malcolm in the Middle' - admitted he already can't wait for the arrival of their first child.

He explained: "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, on the other hand, revealed that she was initially in a state of disbelief after learning about her pregnancy.

She also explained that while the loved-up couple have always wanted kids, they've had to "beat the odds" in order to realise their dream.

Paige said: "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."

Meanwhile, Paige previously hailed Frankie in an Instagram post, describing the actor as the best part of her day.

She wrote on the photo-sharing platform: "You will always be my favorite part of every day. I love you, my husband. (sic)"