As the Cavallari family bands together in preparation for Michael's memorial service, insiders say the troubled star was hoping to turn his life around in the days leading up to his untimely death.
The 30-year-old's struggle with substance abuse and mental health issues may have led him down a troubled path –– he was arrested shortly before disappearing –– but sources close to the family claim that Michael had recently come to terms with making a more permanent change.
"Most recently, Mike felt he wasn't able to maintain sobriety alone and needed to go into a rehab facility," an insider recently told PEOPLE. "He told his mom this as soon as he was released from his detainment."
As RadarOnline.com previously reported, the San Clemente, California, native was last seen at a Utah gas station on Nov. 27. His Honda Civic was found abandoned off a nearby dirt road with the motor still running.
Meanwhile, sister Kristin shared to Instagram followers that the arrival of newborn daughter Saylor has kept her going through this difficult time.
"My little angel, Saylor. She has been my light throughout this whole thing and has given me so much strength," Cavallari wrote alongside a photo of her daughter's feet. "Thank you baby girl for coming when u did."
Just a few days before, the former reality star paid tribute to her brother.
"My heart is in a million pieces. Mikey, I could always count on you to make me laugh," she wrote after learning the news of Michael's passing. "You had such a good heart and will be forever missed. I'm at a loss for words but I know u are in a better place and finally at peace. I love u so much RIP."
Now, the Cavallari family continues to prepare for Michael's service, though plans may hinge on Kristin's ability to travel with newborn Saylor.