The Kardashians are continuing to stand by Lamar Odom.

As several of the Kardashian-Jenner women were spotted leaving Las Vegas on a private jet on Thursday, Kourtney Kardashian shared a social media message for the former NBA star.

WATCH: Lamar Odom's Ex Joins Khloe Kardashian at Hospital

"Believing in the power of prayer for this beautiful soul," she captioned a photo of a smiling Odom, embracing Kourtney's young son, Mason.

Believing in the power of prayer for this beautiful soul. pic.twitter.com/r4u4IM3PWT

— Kourtney Kardashian (@kourtneykardash) October 15, 2015

WATCH: Kardashian Pal Lance Bass Gives Lamar Odom Update: 'The Family Is Devastated'

As ETonline recently reported, security has been tightened at Sunrise Hospital in Las Vegas, where Odom remains in critical condition since being found unconscious at the Love Ranch brothel in Crystal, Nevada on Tuesday.

Khloe Kardashian, who, despite filing for divorce in 2013, remains legally married to Odom, has been keeping vigil by his bedside. Her older sister Kourtney was among the many family members on hand to offer support.

Though he has not been spotted in Las Vegas, Rob Kardashian shared a heartfelt tribute to Odom on his Instagram account on Wednesday night. "Praying nonstop for my brother," he wrote.

Kardashian-Jenner matriarchKris Jenner also asked followers to "Please pray for Lamar," while Kylie Jenner offered a similar sentiment.

WATCH: Lamar Odom's Ex Breaks Silence With a Tupac Quote

Kendall Jenner tweeted simply, "Please don't go."

please don't go.

— Kendall Jenner (@KendallJenner) October 14, 2015

For the latest on Odom's condition, watch the video below.