Kylie Jenner ''cries herself to sleep'' because of bullies.

The 'Keeping Up With The Kardashians' star reportedly struggles to ''brush the haters off'' like her half-sister Kim Kardashian West, leaving her incredibly upset.

A source told HollywoodLife.com: ''Kylie still gets hundreds and thousands of hurtful comments and messages on social media from cyber bullies and she still cries herself to sleep.

''Kylie puts up this tough exterior but it really gets to her. Unlike Kim who brushes the haters off, Kylie takes it really personally. It's hard to have much sympathy for her since she's rich and beautiful, but inside she often struggles with the criticism that comes with being famous.''

Meanwhile, the 17-year-old star recently claimed she had been bullied by the ''whole world'' since she was nine-years-old.

In the video posted on Snapchat, she said: ''It's kind of crazy I have four million people watch my Snapchats. Half of you guys think I'm weird, and the other half think I'm funny. But I've been bullied since I've been nine. From the whole world, it feels like sometimes... and I think that I've done a really great job in handling all this.

''There are bullies everywhere. So, this was just a little like Snapchat, to tell whoever with their own bullies, that the only opinion that ever really matters is yours and to never change. This isn't a pity party though, don't get it twisted. This is for those with bullies out there to know that you're not alone... Spread love. Love y'all.''