"Anytime you lose somebody, obviously it makes you appreciate everyone you have in your life."
"I definitely have been closer with my parents and my entire family in general," she added. "It makes you appreciate everyone you have."
Michael was discovered dead at age 30 outside Salt Lake City, Utah, on Dec. 10 after being reported missing a few days previous.
Cavallari had given birth to her third child, daughter Saylor, on Nov. 23.
"I did at the time, and I still do find a lot of strength in my children -- especially Saylor, just because of the timing of everything," she told Us Weekly on Thursday.
"You can't just stay in bed and feel sorry for yourself. You gotta get up. You have other lives you have to take care of. You got to put food on the table. You got to get them dressed and off to school," the star added.
The television personality said at the time that she has "good and bad days," but has "really found a lot of strength in [her] kids."
"I had Saylor at the same time my brother went missing and ultimately passed away. 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," she said.
Cavallari is known for starring on the MTV series "Laguna Beach" and later "The Hills," which ended in 2010 after a six-season run.
She married NFL star Jay Cutler in 2013, and also shares 4-year-old son Camden and 2-year-old son Jax with the Chicago Bears quarterback.
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