Is it a case of sibling rivalry gone too far? Reality-TV star Rob Kardashian posted a disturbing image to Instagram, calling out his big sister Kim Kardashian in what seems like a either a big joke or a very chilling insult.

Rob, 28, uploaded a photo of actress Rosamund Pike drenched in blood as her character from the hit thriller Gone Girl. The caption stated "This is my sister Kim."

Rob and Kim during happier times Photo: Getty Images

In the film, Rosamund's character is far from being the heroine. Spoiler alert: she's a manipulative wife who fakes her own death, murders her ex-boyfriend and tries to set up her innocent husband.

Adding to the bizarreness of this post, Rob deleted every other picture on his account except this one.

This is my sister kim , the bitch from Gone Girl,,,

A photo posted by ROBERT KARDASHIAN (@robkardashian) on

Rob has been clearly struggling with some issues, one of which revolves around his insecurities regarding his weight. It's thought that's the reason he pulled out of Kim's wedding to Kanye West at the last minute.

Kim later explained that her brother sent her a long email on the morning of the ceremony to explain why he didn't feel able to go, partially blaming the paparazzi and insensitive commenters on the internet.

Rob has been dealing with weight issues Photo: Getty Images

Shortly afterwards, Kris Jenner revealed that he was trying to work through his problems, adding: "My job is to be there for him and love him as hard as I can."

On his birthday on March 17, Khloe congratulated Rob on Instagram with a throwback picture at a birthday party in Las Vegas, saying: " I know this is the year where you will find your happiness again! I will be right by your side, holding your hand, every step of the way!!!"

Kim posted a similar image, saying: "I remember this Vegas party of yours like it was yesterday! I love you so much and can't wait to share so many more memories with you! Kiki loves Riki."

Here's hoping the high-profile siblings work it out!

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