holly montag Credit: John Shearer/Getty Images

Aunt Heidi and Uncle Spencer's little ninja! Proud new mom Holly Montag shared a brand-new photo of her baby son, Isaiah Hawk Wilson, via Twitter on Monday, May 25.

"Super ninja baby!" Heidi Pratt's big sister wrote, alongside a snap of little Isaiah wearing an orange striped onesie by Bebe au Lait and resting his back against a quilted blanket. He looks to the side with a mildly befuddled expression and curls his little fingers into a tiny fist.

Us Weekly confirmed that Holly, 31, welcomed her first child with her husband Richie Wilson on May 3. Baby Isaiah weighed in a 7 pounds and 5 ounces.

"I have never been more in love," Holly shared days after the news was revealed. "@wichierilson and I are beyond blessed that our angel Isaiah chose us to be his parents. Thanks for the love!"

She and Wilson married in September 2014, and announced their pregnancy to Us in January. In the interim, her reality star sister told Us Weekly that witnessing her sister's pregnancy made her reevaluate having kids.

"I was like, 'I think I can put this off for a little bit because you look really uncomfortable,'" the Hills alum told Us in March. "I was like, 'I’m three years younger. Maybe I can wait three more years to catch up.'"

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