The 53-year-old model and her 37-year-old husband, Tokio Hotel guitarist Tom Kaulitz, splashed out on a red Ferrari F430 worth more than six figures, to celebrate his milestone birthday on Saturday.
A video shared on Instagram shows a stunned Henry walking out of the family home with his stepdad and seeing the flashy sports car waiting for him in the driveway.
"Oh my God! Jesus Christ. I don't even know what to say," Henry said when he caught a glimpse of the Ferrari.
Recording the special moment, Klum said: "I can't believe it is that time. You've been waiting for so many years."
As Henry marvelled at the vehicle, Kaulitz explained he bought the car at an auto show in 2025 and hid it in the garage.
"This thing is beautiful. Holy shit! Oh my f***ing God, this … is insane. Holy shit, this thing is crazy.," Henry said.
Klum noted that Kaulitz "kept his promise" after losing a video game bet to a 14-year-old Henry, which meant he had to buy his stepson a Ferrari when he turned 21.
"Literally, it's what? Seven years ago when you guys said that," she said.
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