Khloe's best friend, Malika Haqq, also took to Instagram to mourn Jamie's death, posting a throwback photo of the two of them alongside the former couple. "Thru good and bad times life shows us every spirit matters and leaves a print on the hearts of others after they have passed... RIP Jamie Sangouthai #GodHelpUsAll," she wrote.
Jamie was close friends with Lamar, 35, since high school. He served as one of the NBA star’s best men during his 2009 wedding to Khloe.
"Lamar is beside himself. This is the worst tragedy," a source tells Us. "They were best friends, like brothers."
"Lamar is going to take this really hard," another source adds.