"When Audrina was pregnant, she reached out a lot and asked me some questions, like what pregnancy jeans I liked, and that kind of stuff," Cavallari said of Patridge, who welcomed daughter Kirra in June 2016.
"I've talked to her since she's had the baby and she sounds like she's just loving life."
"For Heidi, I put together a little list of different products and toys that I've loved and sent that over to her," she added of Montag, who is expecting a baby boy in the fall.
"I have three kids and what I've learned is, each baby is so different," the star shared. "And every family, every person is different. So I say, be open-minded, but at the end of the day you really have to do what you think is best, and really trust your gut feelings."
Cavallari herself shares 4-year-old son Camden, 3-year-old son Jax and 19-month-old daughter Saylor with her husband, NFL star Jay Cutler.
"My boys are close in age, so one minute they're best friends and one minute they're hitting each other," the star said. "[But] they're so sweet, they're incredibly loving, and they love to cuddle and they love their mommy."
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"There's a different bond [with Saylor]," she added. "She's a diva, but she's a ton of fun ... She's pretty tough. She's getting down and dirty and isn't afraid to roughhouse."
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