The former Hills and Laguna Beach star looked stylish in co-ords while attending the Style 360 party on Thursday night (11 September).
Kristin, 27, gave birth to second son Jaxon Wyatt Cutler on Wednesday, 7 May. She's also mum to son Camden Jack, two.
The blonde reality star is married to American footballer Jay Cutler, who is currently signed to the Chicago Bears.
Kristin recently gushed about his daddy skills in an interview with Michigan Avenue magazine, saying: "He's incredibly hands-on, and he has been since day one. It's so sweet seeing him with Camden and Jax, and there's nothing sexier than seeing your husband as a great dad. I couldn't ask for a better partner in this situation."
Since leaving The Hills, the star has made a name for herself in fashion, launching her own shoe line with Chinese Laundry.
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Stars who welcomed babies in 2014:
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