Michael Cavallari's Family Planning Memorial as Source Says He Was Considering Rehab

"Mike felt he wasn't able to maintain sobriety alone and needed to go into a rehab facility," a source close to the family PEOPLE

Photo: Courtesy Grand County, Utah, Sheriff's Office

Michael Cavallari was hoping to get help for personal struggles shortly before he went missing the day after Thanksgiving.

Friends tell PEOPLE that Cavallari battled alcohol addiction and dealt with mental health issues, but a family source says he was “really turning his life around” and working with his father Dennis doing real estate development before his death.

“Most recently, Mike felt he wasn’t able to maintain sobriety alone and needed to go into a rehab facility,” a source close to the family tells PEOPLE of Cavallari, who was arrested shortly before he disappeared. “He told his mom this as soon as he was released from his detainment.”

The mourning family is planning a memorial service for Cavallari, but they are waiting to see when his sister Kristin Cavallari‘s newborn daughter Saylor would be able to travel, the source adds.

Cavallari’s body was discovered in Utah Friday nearly two weeks after he was reported missing. Officials said his body was found in the Salt Wash area near exit 175 on I-70 in Grand County, which is described as having steep and rocky terrain. He went missing Nov. 27 after abandoning his car off the highway. And a day earlier, he was arrested in Orange County and briefly held in jail.

RELATED VIDEO: Kristin Cavallari’s Touching Tribute to Brother Michael: ‘You Had Such a Good Heart and Will Be Forever Missed’

On Monday, Kristin, 28, posted a touching Instagram tribute, thanking her daughter for helping her get through the loss of her brother.

“My little angel, Saylor. She has been my light throughout this whole thing and has given me so much strength. Thank you baby girl for coming when u did.”