Khloé Kardashian skipped her sister Kim Kardashian West's birthday bash in order to stay at Lamar Odom's bedside.

Khloé Kardashian

Khloé Kardashian

The 31-year-old reality TV star reportedly turned down the opportunity to attend her older sibling's 35th party yesterday (21.10.15) because she didn't want to leave her estranged husband Lamar Odom following his collapse last week.

A source told UsWeekly magazine: "Lamar isn't doing that well. He can't stand up by himself. She is still very worried about him and uncomfortable with leaving."

The 'Keeping Up With the Kardashians' star, who recently decided to move Lamar from Sunrise hospital in Nevada to a rehab facility in her home city Los Angeles, hasn't left the 35-year-old basketball player's side since he was admitted to hospital in Las Vegas after he was found unconscious at nearby brothel following a four-day drugs and alcohol binge.

It's thought Lamar is being treated for aspiration pneumonia, which develops after food, liquid, or vomit has been inhaled, but is making a good recovery and is able to speak in full sentences and swallow his food without assistance now.

The results of his CT scan are said to have come back normal but he will reportedly remain on dialysis, a procedure to remove waste products and excess fluid from the blood when the kidneys stop working properly, for a little longer.

Meanwhile, Khloé has called off her divorce from Lamar because she doesn't want to "make any big moves" during his recovery and felt it was "the most sensible thing to do."

Khloé filed for divorce from Lamar in December 2013 following months of rumours he was addicted to drugs and cheating on her, but she delayed signing the papers until last summer in the hope of rekindling their relationship.