Rob's weight has come under increasing scrutiny over the years and the US reality star has found himself being teased by trolls as he battles to keep in shape.
However, after sharing an old photograph of himself on Instagram, which was taken several years ago, Rob has shrugged off the bullies and hinted that he accepts his current size.
Commenting on the black and white snap, Rob said: "Last throwback of the day and yes I'm fat now so yall haters can literally suck d***."
Rob's defiant stance has received praise from his followers, with one telling the sock designer: "#ROCK the #big #man status CUZ honestly a lot of women like a #big #juicy #man. It just feels safe inside a bear hug... Just saying.."
Another fan added: "Still the same person Rob! Big or small, still the same."
Rob's weight has increasingly gone up over the years and, as a result, he has kept himself out of the limelight.
Last May, when sister Kim and rapper Kanye West tied the knot in Italy, there were reports that Rob had left the wedding party early and flown home to the US because he felt self-conscious about his size.
Following the bash, his mum Kris gave an interview to E! and said: "Rob is living in LA and doing well. He's finding out what makes him tick and is struggling with some stuff.
"My job is to be there for him. Everybody goes through stuff and we get through each other's adversity."
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