The 28-year-old has spent nearly two years away from the cameras, battling depression and gaining more than 100 pounds. And on Tuesday, the youngest – and only brother – of the Kardashian clan was hospitalized, with some reports citing his diagnosis as diabetes.
"Rob had stomach problems over the weekend and didn't feel well. He was at the hospital briefly," a source told PEOPLE. "He has to take medicine now to control his blood sugar level."
"He was also told he needs to rethink his whole lifestyle," the source added. "He needs to see a dietician and change the way he eats. If he doesn't change his lifestyle, he was told that it could have serious consequences."
Despite encouragement from his family, Kardashian has had trouble getting back on his feet.
"Rob is still struggling and it makes the family sad," a source told PEOPLE earlier this month. "He deals with depression, weight issues and low self-esteem, but that's been going on for a long time."
His hardships began a few years after he competed on Dancing with the Stars in 2011. Recently, his most public displays have come by way of his Instagram account.
After a lengthy hiatus from social media, Rob returned in March, posting a photo of Rosamund Pike as Amy Dunne in Gone Girl, calling sister Kim Kardashian West "the b---- from Gone Girl."
That same month, a source told PEOPLE the famous family tried to stage multiple interventions – some later shown on camera – that failed.
"He is very against therapy and any kind of rehab," the KUWTK production source said. "But his family will continue to push for him to get help until he does."
Rob has also used his return to social media to mark his progress, posting about workouts with his sisters and beach trips.
A Keeping up with the Kardashians source told PEOPLE in September that "Rob has already lost a lot of weight and seems much healthier mentally as well."
But Kardashian isn't just avoiding the spotlight: He's been absent from several family events, including Kim's wedding.
In an interview for her PEOPLE cover story in October, Khloé Kardashian spoke of her attempts to get her little brother – who lives with her – to be more social and healthy.
In recent weeks, Khloé and Kourtney Kardashian have both shared sweet Instagram snapshots to encourage the troubled star.
However, the family knows that Rob's journey is all his own.
"It's sad, because he's only wasting his life more and more," Khloé said. "But he has to figure it out for himself. And he has so many people who want to help him."