PHOTO: Miranda Kerr Back to Work – and Breastfeeding

By Alla Byrne

04/29/2011 at 05:00 PM EDT

Breastfeeding seems to be doing wonders for new mom Miranda Kerr – she posted a photo of herself nursing 3-month-old son Flynn while at a shoot for Victoria’s Secret on Thursday.

The Australia beauty looked camera-ready while lounging backstage in a silky robe, red stilettos and wavy hair.

"Another day in the office. Back to work for VS. Flynn is with me on set! Lil cutie pie Xxx,” Kerr, 28, Tweeted.

The supermodel, who gave birth to her son with Orlando Bloom on January 6, is already back in catwalk shape.

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After a surprise return to the runway in March, Kerr was back in beachwear earlier this month, where she showed off her trim and toned figure in a bikini by Have Faith during a photo shoot in Malibu.

What does her husband Bloom think of her post-baby body?

"It's genetics,” he said on The Ellen DeGeneres Show on Friday. "It's amazing. She looks incredible.”

When DeGeneres asked how she got back into shape so quickly, Bloom, 34, responded, "A lot of breastfeeding."

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