Olivia Flowers is opening up about her brother Conner Flowers' unexpected death.

According to the Southern Charm star, the coroner ruled that her 32-year-old sibling died from an accidental overdose of fentanyl on Jan. 30, years after being prescribed opioids to treat chronic pain stemming from his longtime battle with Lyme disease.

"My brother hated talking about his illness," she told People in an interview published Nov. 1. "So many people, even in his close circle, didn't know about his Lyme."

Lyme disease is an illness caused by the borrelia bacteria that is commonly transmitted through the bite of an infected tick, according to the Centers of Disease Control and Prevention. Symptoms range from fever, headache and fatigue to serious infections in the heart and nervous system if left untreated.

Olivia said "debilitating" symptoms of Conner's Lyme disease first surfaced when he was 15. Though the family quickly sought help from various medical professionals, she recalled that "Conner was just told over and over, 'It's all in your head, you're fine'" and was given  painkillers and medicine for his associated anxiety instead.

"He started depending, at a very young age, on this prescription medicine to feel normal," Olivia remembered. "And we as a family started to see this toll it took on his body."

As he struggled with his symptoms, Conner became addicted to the prescription medication he thought was helping him, according to Olivia. And when her brother finally found a specialist who could help him with his disease, Olivia said the illness had caused so much internal damage to his health that "not only was he getting treatment for Lyme, but he was also in rehab dealing with getting off this medicine."

"Nobody wanted to get better more than Conner did," she shared. "It was just such a hard time. We are very, very close as a family. We were all very involved and rallied round him. But for years he was just in and out of rehab, trying so hard to get on the other side of this."

Olivia continued, "People, when they hear words like 'rehab' or 'drugs,' they assume the worse. But these weren't substances he turned to for partying. This was medicine. This is what made him feel normal."

The Bravo personality said Conner was "completely clean" just weeks before his death, when the family traveled to Arizona to visit him at the wellness center where he was staying. "He was in the best shape I'd seen him in years," Olivia recalled. "He had huge dreams he wanted to accomplish. And he was talking about his plans to move to Dallas, Texas, where he already had jobs lined up."

The siblings were supposed to meet up for dinner at the family's South Carolina home in late January, just a week before Conner's 33rd birthday. However, Conner never showed up.

"It was just so crazy," Olivia said of her brother's passing. "We were on the phone not even an hour earlier. And then... he's gone."

Olivia shared that Conner had a relapse that turned fatal. "So again, to hear he died of a fentanyl overdose, there's immediately going to be this assumption that he was partying," she said. "Conner wasn't like that. This was his means to survive."

Calling the loss "heartbreaking," Olivia added, "There are these holes in the healthcare system, and my brother fell into one."

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