Kristin Cavallari on Brother's Death: 'I Found a Lot of Strength in My Children'

Kristin Cavallari stopped by "GMA" to discuss her new book.

— -- Kristen Cavallari said she’s leaning on her loved ones following the sudden death of her brother, Michael.

Michael went missing shortly after Thanksgiving and his car was found abandoned by Utah authorities, according to the Grand County’s Sheriff’s Office. His body was discovered on Dec. 10.

A medical examiner later determined that Michael died of hypothermia in rural Utah after he crashed his car in frigid temperatures shortly after Thanksgiving, the AP reported.

The former "Laguna Beach" and "The Hills" star recently gave birth to Saylor, her third child, and even found time to write a book while balancing her shoe and jewelry lines.

"Balancing in Heels: My Journey to Health, Happiness, and Making It All Work,” focuses on everything from health and wellness, fitness, fashion, recipes and motherhood.

“[Saylor] awesome,” Cavallari said of her daughter. “She’s my best baby…and it’s fun. We have a girl now. Just the energy in our house shifted and it’s really nice…I needed someone on my team.”

"Balancing In Heels" is in bookstores now.