"We're going to drive by Kourt's house blasting birthday music, honking horns, annoying all the neighbors," she explains in the clip. "Everyone did such a great job decorating their cars."
As guests begin to gather in the neighborhood from the safety of their respective vehicles, Khloé, 36, enlists Kourtney's 8-year-old daughter, Penelope, to get her mom outside.
"Penelope, can your mom hear me? Okay, because we have a surprise, so I'm going to need you to do something for me," she says over the phone. "I need your help with getting your mommy out the front door and I'm going to have a surprise for her on the street. You're just going to have to say, 'Mom, can you come outside? I need to show you something.' But don't ruin the surprise! You can take all the credit."
The plan goes off without a hitch, and Kourtney looks genuinely surprised by the lineup of familiar faces as everyone honks and cheers. Cameras even catch Kim Kardashian West's daughter North, 7, waving from the sun roof of a Range Rover.
Keeping Up With The Kardashians/Youtube
A source told PEOPLE at the time that Kourtney "had a fun birthday."
"She was just grateful to wake up with her kids around. She is always the happiest with her kids," the source said. "She received multiple flower deliveries and felt very treated. Her family and friends also celebrated her with a drive-by parade."
Keeping Up with the Kardashians returns Sep. 17 at 8 p.m. ET on E!
Source : https://www.yahoo.com/entertainment/kardashian-family-surprises-kourtney-socially-163620468.html