A Delaware family was shocked when they heard three knocks on their door and someone screaming “abra cadabra.”

When Lynn Staffieri needed a new pet playpen for the kittens her family was fostering, she turned to Amazon, not knowing that her teenage son had set some hilarious "additional instructions" as a default a couple months earlier.

When the package arrived at the family’s Magnolia, Delaware, house last week, they were shocked when they heard three knocks on their door and a woman screaming “abra cadabra.”

By that point, 13-year-old Jacob had forgotten that he had written “knock on the door three times and scream ‘abra cadabra’ as loud as you can and run super-fast away" in the field intended for additional delivery instructions.

"It was just the first thing that came to mind, and I thought it would be funny to hear someone say that," Jacob told CNN. 

The best part? The moment was recorded by the family’s front-porch Nest camera. What they saw when they watched it made their day.

"(Jacob) was cracking up. He thought it was the funniest thing. He didn't think that anyone would do that," Lynn recalled to CNN. "I thought it was great. It gave us such a laugh."

She posted the video on Facebook, where it quickly went viral.

“It made us smile even though my son should not have done that, so I apologize for that,” Lynn wrote alongside the video. “I do appreciate that the driver looked closely enough at the instructions though because I know a lot of people wouldn't.”

Lynn told CNN that she hopes the Amazon delivery woman knows that she made thousands of people laugh.

"I'm sure that the jobs of essential workers have been so tough, and people have been ordering a lot of stuff, so she must have been busy," she said. "But for her to have the energy and attention to detail, it just put a smile on our faces."