"I was friends with your ex," the pair mouth. "You were with him when we met. Guess he hasn't found out yet, but I know he's gonna kill me when he sees me with you."
Kourtney Kardashian is supporting her stepson Landon Barker to help the aspiring musician promote his new song.
In a TikTok video Landon, 19, posted, the pair sing along to his new track "Friends With Your Ex."
Kourt, donning a Betty Boop tee and a no-makeup look, lip syncs the words next to her step son.
"We had to run it up!" Landon captioned the video, also tagging his stepmom.
"I was friends with your ex," the pair mouth. "You were with him when we met. Guess he hasn't found out yet, but I know he's gonna kill me when he sees me with you."
Kourtney Kardashian Shares 'Empowering' Pregnancy Photos After Emergency Surgery
View StoryKourtney and Landon's father Travis Barker got married in 2022 after dating for one year, starting in 2021, blending the pair's respective families together.
Kardashian is currently pregnant, and the pair recently opened up about going through emergency surgery.
Kardashian took to Instagram to reveal that she had undergone "urgent fetal surgery" to save her baby's life.
Sharing a black-and-white hospital photo of her hand in Barker's, the mother of three said she's "forever grateful" to the doctors, her husband for rushing home from his tour with Blink-182 last week to be by her side, and for her mom, Kris Jenner, for supporting her through this traumatic time.
"I will be forever grateful to my incredible doctors for saving our baby’s life. I am eternally grateful to my husband who rushed to my side from tour to be with me in the hospital and take care of me afterwards, my rock. And to my mom, thank you for holding my hand through this," Kardashian, who sported a small bandage over her pregnant belly, wrote.
Barker is a father to Landon along with Alabama, 17, and step-daughter Atiana De La Hoya with ex Shanna Moakler. Kourtney also shares Mason, 13, Penelope, 11, and Reign, 8, with ex Scott Disick.