Kourtney Kardashian looked fittingly glowing late last week as the brand-new mother-of-two made her way to Nobu in Malibu, where she and her family celebrated stepsister Kylie Jenner’s 15th birthday.

Kourtney — who gave birth to daughter Penelope on July 8 — showed off her incredible post-baby body on her way inside, donning a blue polka-dot and slimming black pants.

Her cutest accessories, though? Son Mason, 2, who held onto his mommy’s hand, and little Penelope, whom Kourtney’s partner, Scott Disick, kept shielded from the paparazzi in a portable car seat.

Also on the scene: the birthday girl herself, Kylie, who was seen carrying a whole bunch of presents to the car.

Kylie Jenner Fetes Her 15th Birthday With Family

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Last Wednesday, Kourtney, 33, introduced Penelope to the world on the cover of Us Weekly. You can check out the photo by clicking here.

What do you think of Kourtney’s post-baby body? Sound off in the comments, below.