He's going to be in a world of trouble for this stunt...
Rob Kardashian has done the one thing you're not supposed to do to your famous siblings - he's put half-sister Kylie Jenner on speed dial to the whole of the internet.
The reality TV star flipped out when he realised that his family had been organising a baby shower for him, but had not invited his pregnant fiancee Blac Chyna. You know, the actual person having the baby.
Hell hath no fury like a Kardashian scorned, and Rob decided to wreak his revenge in the most vicious way he could think of - by revealing Kylie's mobile number, followed by a series of laughing emojis and the confirmation: "I ain't hacked either this is rob dog lol".
One fan saw his chance and grabbed it with both hands.
Things have previously been awkward between the siblings as Blac Chyna's ex-fiance Tyga, who she has a three-year-old son with, has been in an on/off relationship with Kylie for the past two years.
It seemed Rob hadn't exactly endeared himself to his in-laws either, though, as in the most recent episode of the E! spin-off series to Keeping Up With The Kardashians, Rob & Chyna, he got an ear bashing from Chyna's mum Tokyo Toni.
She demanded: "When you going to get married? You gotta stop what you're doing. (Chyna) don't need a baby she needs (you to be) a father...You can't do what you're doing. You're going to ruin it."