Khloé Kardashian sends emotional message to brother Rob on Instagram

Gemma Strong

Khloé Kardashian has sent a short but poignant message to her brother Rob Kardashian. "It's simple… I miss you," the 31-year-old wrote alongside a throwback photo of the siblings together, adding three crying emojis next to the black and white snapshot of Rob giving her a kiss on the cheek.

Khloe's messages comes as Rob's new romance with Blac Chyna continues to blossom. Since the pair started dating, 28-year-old Rob seems to have emerged from his self-imposed exile, and has been looking noticeably slimmer in recent weeks.

It's simple..... I miss you 😫😫😫

A photo posted by Khloé (@khloekardashian) on

Khloé Kardashian sent a heatfelt message to her brother on Instagram

On Thursday, Rob and Blac were photographed leaving a gym together after a workout, and later that same day, the smitten TV star beamed a huge smile as he posed in a Snapchat video with his girlfriend, with fans remarking how much happier he now looks.

But, while Rob's romance with Blac is going from strength-to-strength, his relationship with his sisters seems to have hit a rocky patch.

Khloé in particular is said to be struggling with her brother’s new situation – she and Rob are very close, and lived together for much of the time he was struggling with his weight and with depression.

khloe-rob-

Khloé is said to be unhappy about her brother's romance with Blac Chyna

"Khloé feels majorly betrayed by Rob after she always stuck up for him," a source told Us Weekly. "She feels like this is a major blow to the family. Nobody in the family likes it."

Indeed, in late January a family friend told E! News that Khloé , Kim and Kourtney are all "livid about the relationship and not supportive of it at all."

A second source added: "All the sisters are united and think Rob is being disloyal. They want him to be happy and they're so over the whole thing."