Rob, who was recently hospitalized, has received plenty of love from his sisters on social media this year

By Lindsay Kimble
December 30, 2015 05:00 PM

Rob Kardashian spent most of 2015 as a recluse amid weight gain and a struggle with depression, but at least one aspect of the star’s life has been public: the support of his siblings.

News broke Tuesday that Rob, 28, had been hospitalized, with some reports citing his diagnosis as diabetes. His mother Kris Jenner flew back from vacation to attend to her son.

The setback is just the latest in a string of struggles for the star, but through it all, his sisters have remained encouraging – especially on social media.

Following Rob’s hospitalization, Khloé Kardashian, who has been among his biggest supporters on social media, shared a somber looking photo of herself, captioning it “Melancholy.”

Earlier this month, Khloé shared an old photo with her little brother, 28, writing, “if only you could see yourself through my eyes.”

She continued, “I’ll forever be obsessed with you! My one and only! #MyAce.”

A few days later, Kourtney Kardashian followed suit, also posting a bittersweet throwback to Instagram.

“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.”

The source added that, “the family, especially Khloé, is very much there for him but it has to be his own journey to figure out.”

Khloé, in particular, has been vocal about Rob’s troubles.

“Rob is such a great guy,” she told PEOPLE in her October cover story interview. “He’s charming, charismatic, everything. That’s what’s so infuriating. I’m like, ‘Where is your will to live life? Let’s be around people!’ ”

Rob has skipped out on a number of family events over the past several years, including even sister Kim Kardashian West‘s wedding.

“I’ve been working on my patience,” Khloé continued in the October PEOPLE interview. “I’ve been really trying. But I have my moments and I do snap. I’ve offered to get a chef, I’m like, ‘What’s your excuse?’ But it’s not just that. I can’t win life for Rob. I have to wait until [he’s] ready to do it for himself.”

Earlier this year it appeared that Rob, who lives with 31-year-old Khloé, was working on getting and shape and joining his siblings at the gym.

“I think he’s just going through a phase where he’s not comfortable in his own skin,” Kim said in April. “He is working really hard to get back to where he really wants to be.”