Speaking on E! News on Thursday she said: "Rob is living in L.A. right now, he is doing well, finding out what makes him tick. He is struggling with some stuff but my job is to be there for him and love him as hard as I can.
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"Everyone goes through stuff and we get through each other's adversity one year at a time."
Unlike the rest of the Kardashian clan, Rob, 27, has recently maintained a low profile. He surprised celebrity followers when he skipped his sister Kim Kardashian's wedding to rapper Kanye West in Florence, Italy.
Having flown to Europe with his family, Rob is understood to have booked a last-minute flight home after having an argument with the bride-to-be.
According to website X17, a row broke out when Kim asked family members to wear Valentino couture for a pre-wedding lunch at the Italian designer's house.
Rob is said to have been unable to fit into any of the clothes, which led Kim to criticise him for making "no effort to drop any weight over the past months".
"Rob basically equated that to Kim caring about him only for his appearance and he said he'd 'make life easier' for her and just leave," a source told the website.
The sock designer has been rumoured to have been feeling low for several months now. In April he was admitted to rehab for the treatment of depression, according to reports.
Just this week he seemed to be sending out a message via the Twittersphere, unfollowing everyone except for his mum Kris Jenner and sister Kylie Jenner.