Stay-at-home dads are becoming the new trend Down Under, with Nine's first episode of drama series House Husbands ranking as the number one show in the country on Sunday night.

It seems it is a case of life imitating art this week for glamour couple Miranda Kerr and Orlando Bloom.

While Kerr was in Sydney yesterday launching a new hair-care range, her actor husband was seen playing dad to their 20-month-old son, Flynn.

The Lord of the Rings actor and Flynn had a boys' day out, with Bloom pushing the cute youngster around the streets of Sydney. Bloom's casual outfit and scruffy hair were a far cry from his wife's glamorous outfit for her appearance at The Palm House at Sydney's Royal Botanic Gardens.

"I love it," Bloom said recently of being a hands-on dad. "I hate that word but I love being a father."

Following their stint in Australia, the couple will head back to their home base in New York where Bloom is set to play Romeo in a Broadway adaptation of Shakespeare's Romeo and Juliet.