Balancing in a bikini! Kristin Cavallari shared a photo of herself preparing to pump breast milk on Thursday, April 7, while lounging in her skimpy swimsuit in some luxurious outdoor space.

"Thank you @inspirato for this gorgeous view while I pump," the Laguna Beach alum, 29, wrote alongside a photo of herself smiling and holding a device. "#DutyCalls #Inspirato." In the snap, Cavallari wears a cute striped bikini by Melissa Odabash and Illesteva sunglasses.

The star enjoyed some sunshine and relaxation on Thursday after a busy month of promoting her new book, Balancing in Heels. In the part-lifestyle, part-memoir guide, Cavallari went into detail about the topic of breast-feeding — and how she and her husband, Jay Cutler, preferred to wean their sons, Camden, 3, and Jaxon, 23 months.

"I'm not a fan of soy (it's usually genetically modified; more about that later), and both Cam and Jax have sensitivities to cow's milk," Cavallari wrote. "And unfortunately, soy and cow's milk are the only two options for store-bought formula available right now. Goat's milk is the closest thing out there to human breast milk. Plus, it is more easily digested than cow's or soy milk." The couple and their pediatrician came up with a custom formula comprised of goat's milk so that their sons would receive the proper nutrients.

Their youngest child, daughter Saylor, meanwhile, continues to breast-feed at 4 months. In Balancing in Heels: My Journey to Health, Happiness, and Making It All Work, Cavallari also opened up about sacrificing sleep and hygiene to care for her little ones.

"In the early months, I went days without washing my hair and wore the same yoga pants until they started to smell," the reality star shared in her book. "On days I was alone, I wouldn't brush my teeth sometimes until Camden took his first nap. Who am I kidding? That sometimes still happens when I'm alone with the kids!"

Still, she would do it again. "While I'm not exactly proud of these moments, I do realize that 'letting go' is another way of prioritizing our family's overall happiness over the day-to-day mess. In that regard, I am happy to be a bum for a day or two!" Cavallari dished. "Accepting that change has been freeing and made my life less stressful."

Watch her make her favorite quinoa dish in Us Weekly's exclusive video above. 

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