Kim Kardashian has ''no sympathy'' for her brother Rob.

The sock designer, 27, has plunged into depression after piling on the pounds, but the 33-year-old beauty doesn't feel sorry for him and thinks he needs to stop moping and do something to improve the situation.

Speaking in last night's (20.07.14) episode of 'Keeping Up With the Kardashians', she said to her sister Khloé, 30, after Rob failed to attend a family vacation to Thailand: ''We've all been here to offer him help and he won't take it, so I don't have sympathy.''

Kim then turned to the camera and explained: ''I think I'm just more of the tough love kind of person. My personality is like, 'All right, you complain, you don't like it, get up and do something about it.' ''

However, Khloé insists Rob's weight gain isn't the only thing that has pushed him into depression as he also struggled to deal with the brunette beauty's split from estranged husband Lamar Odom last year.

She said: ''Rob has deeper issues than just weight.''

Meanwhile, Kim and Rob reportedly haven't spoken since he refused to attend her wedding to Kanye West in May after she mocked his recent weight gain.

A source said previously: ''Kim and Rob haven't been speaking to each other for months -- she thinks he is lazy, and bringing down the family name because of his physical appearance.''