Kristin Cavallari recently learned a very important lesson: S‑‑t happens. “I went to Target with all three children,” the mom of Camden, 4, Jaxon, 2, and 13-month-old Saylor told Us Weekly Video, “and as I’m pulling Saylor out of her car seat, I realized she had had a massive blowout everywhere. She had poop all the way up her stomach, all the way up her back, and of course I didn’t have a diaper or a wipe.”

Next time, the Balancing in Heels author, 29, will be more prepared. She now never leaves home without a pack of Babyganics wipes! Other diaper-bag must-haves: Boudreaux’s Butt Paste, ponytail holders for Saylor, the GFB gluten-free protein bars and Cocokind’s organic rosewater facial toner — a product that keeps Camden and Jaxon occupied better than any toy. “This is pure entertainment for both my boys,” Cavallari told Us. “They just sit there and spray their faces.” Watch Cavallari unpack all her mom essentials in the video above.

The Laguna Beach alum, who shares her kids with Chicago Bears quarterback husband Jay Cutler, says Camden and Jaxon dote on their little sister. “They definitely instinctually know and kind of pick up on that she’s a girl and they’re sweeter with her,” she told Us at a Young Living Essential Oils event in New York City on December 7. “The boys will hit and punch each other all day long, but they’ve never hurt Saylor. They’re so sweet and sensitive with her. It’s really nice to see.”

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