Hilary Duff / Twitter 1 / 14
Hilary Duff / Twitter 1 / 14

Now that Hilary Duff has made her post-baby debut, she felt it was time for her new son, Luca Cruz, to make his debut as well!

On Monday, the 24-year-old first-time mom posted a photo of Luca's tiny feet to her Instagram account.

"My favorite little feet," she gushed in the caption.

PHOTOS: How Hilary went from a child star to a mommy

Since welcoming her and hubby Mike Comrie's first child March 20, the "Lizzie McGuire" star has been keeping busy.

PHOTOS: Biggest celeb pregnancies

On Thursday, she stepped out for some pampering at West Hollywood's Nine Zero One salon while wearing skin-tight leopard skinny jeans and a purple top.

PHOTOS: Incredible post-baby bodies

On Saturday, just one and a half weeks after giving birth, she hit the gym to tone up her post-baby bod.

"20 minutes on the elliptical seems like an eternity!!! What the hell…" she tweeted about her first workout since giving birth.

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