She had seen videos all over the internet of horses in the drive-thru lane, but when the Arizona teen and her horse Scout gave it a try, the barista wasn't about to allow any horsing around.
"We weren't given any reason, just 'We can't take your order,'" Cline said. "Me and my friend were going to get Frappuccinos for us and a cup of whipped cream for the horses."
Cline and her family said they were disappointed, but still support Starbucks.
A company spokesperson said officially, the drive-thru is for cars only for safety reasons and that the barista was caught off guard.
The story has a happy ending though. According to ABC News, Cline got a second chance on Tuesday to ride through the drive-thru after a district manager for Starbucks reached out.
"It was pretty exciting, though my horse did try to eat my caramel Frappuccino," Aspen told ABC News.