Unbelievable.
It's safe to say Kristin Cavallari has lost the baby weight and then some.
The Laguna Beach star -- who gave birth to her second child with Chicago Bears quarterback Jay Cutler, son Jaxon Wyatt -- in May, shocked fans during an appearance Monday on Good Morning America with her super-slim physique.
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Wearing a form-fitting light blue Torn by Ronny Kobo dress (which retails for $388) and leopard-print heels from her own Chinese Laundry collection, a side view of Kristin, 27, shows just how fit the mother of two is less than four months after giving birth.
Though not all the reaction to her enviable bod has been positive.
After Kristin posted a photo of herself on her Instagram rocking the eye-catching bodycon dress, it wasn't long before some people voiced their concern.
"YOU LOOK TOO SKINNY," one user wrote.
In 2012, even her Laguna Beach nemesis Lauren Conrad commented on Kristin’s seemingly super-human ability to shed pounds during an appearance on Bravo's Watch What Happens Live.
"She's really good at losing baby weight. That's true!" LC laughed when asked to say three nice things about Kristin. "She is a very pretty girl."
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Last August, mother of four Brooke Burke-Charvet revealed to ET her own surprising tip for losing post-pregnancy weight.
Watch below!