Kristin Cavallari on brother's death: 'I found strength in my kids'

LOS ANGELES, March 16 (UPI) -- Kristin Cavallari says her children have helped her cope with her brother's recent death.

The 29-year-old designer reflected on her sibling's death in an interview with Entertainment Tonight while promoting her new book, Balancing in Heels: My Journey to Health, Happiness, and Making It All Work.

"I'm okay. I have good days and bad days," the star said of the loss. "I've really found a lot of strength in my kids ... I feel for my parents. They've been going through it. But everyone's getting better."

Cavallari gave birth to her third child, daughter Saylor James, on Nov. 23, just days before her brother, Michael Cavallari, went missing. He was discovered dead at age 30 outside Salt Lake City, Utah, on Dec. 10.

"I had Saylor at the same time my brother went missing and ultimately passed away," the designer said. "I couldn't collapse. I had a newborn baby to look after. I had to be strong for her and for my whole family. So that's what I've been doing."

Cavallari and husband Jay Cutler married in 2013 and are also parents to 3-year-old son Camden Jack and 22-month-old son Jaxon Wyatt. The star said she sees a lot of her brother in Camden, whom she described as a "sweet, sensitive soul."

"He had such a good heart. He was just a really good guy," she said of her brother. "He was the only one who could push my buttons the way he did. It was like that brother-sister relationship -- he would make me laugh, then push my buttons, then make me laugh."

Cavallari shared her gratitude and "appreciation for life" with fans in January following her brother's death and a minor car crash. Her book, Balancing in Heels, will address her time on The Hills and her subsequent marriage and motherhood.

Kristin Cavallari shared a photo of her sons checking out her book, "Balancing in Heels," on March 7. Photo by Kristin Cavallari/Instagram