Here's a lesson to all of you Rob Kardashian haters out there. Big sister Khloe Kardashian is willing to lash out at you if you are going to mess with her brother.

Just this week, the "Keeping Up With The Kardashians" star took to Instagram to crush one of her brother's haters. Khloe apparently defended Rob who has been dealing with a lot since his weight gain and now his journey to his fit self via a weight loss routine.

Hollywood Life has learned that big sis came to the rescue after Rob took to Instagram to share an inspiring clip of the late human rights activist Malcolm X. Rob captioned the clip with a cryptic message which read: "I live like a man who is dead already. I have no fear whatsoever of anybody or anything."

Rob's post got a lot of positive feedback from his followers, but one reportedly took the time to slam the elusive Kardashian for comparing himself to the late Minister.

Because Rob didn't address the hater, Khloe stepped in to slam the latter writing: "He is not comparing himself you judgmental f-k." Lamar Odom's ex-wife then continued her strong attack with: "Where did he say he was?!?! He's simply admiring another man's wisdom, strength and courage... Can't one admire another without the stones being thrown. Chill out. Get off my brothers page."

The alleged hater then explained herself to Khloe and apologized. The "KUWTK" star of course accepted the apology and even said that she's happy to hear Instagram user @annofscotland's explanation.

She wrote: "@annofscotland happy to hear that! He gets criticized for being too private and then when he decides to get back on social media he gets attacked. Damned if you do and damned if you don't. Let's uplift one another and not assume. Let's all root for Rob," Fashion&Style quoted.

The news comes amid Rob Kardashian's weight loss transformation, which he the has been teasing about on Instagram. A week ago a shared a black and white photo of his head looking slimmer than usual. Early this week, he also posted a snap of him drinking with his slimmer left arm on full display. Then, just this Friday, he posted a snap of his new hairdo.

Rob's friend Makia Haqq even confirmed to E! News that Kris Jenner's only son is "doing very well." She explained, "He has been working out and taking care of himself. I think Rob shares what he wants to share. I think that's how it should be for everyone. When you're ready you post, post. When you're ready to be seen, be seen. When you don't, leave him alone."