PIC: Aww! See Hilary Duff, Mike Comrie and Son Luca's First Family Portrait

That's one gorgeous family!

Hilary Duff shared a very special photo with her Twitter followers on Thursday--a sweet, black and white portrait of her and husband Mike Comrie posing with their new son Luca Cruz.

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The singer/actress, 24, and her husband of one year welcomed Luca March 20; since then, the proud mama has been tweeting intimate photos of Luca's new life at home.

Less than a month after giving birth, the fitness devotee is already getting back to her pre-baby exercise routine. The new mom was spotted attending a class at SoulCycle's West Hollywood location Tuesday.

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"She looked great, but definitely seemed to be struggling a little," an eyewitness tells Us Weekly of Duff's hard work in spin class.

Still, the challenging workout didn't stop the former Disney star from giving it another go on Thursday.

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"Yaaaaa SoulCycle, ya did it again!" Duff tweeted after class. "Thanks!"