A mother in Atlanta, Georgia who read Marie Kondo and tried to eliminate things that do not “spark joy” faces deep regret after getting rid of her son’s mug, which she later discovered to contain thousands of dollars.

Devon Silvey, 27, was in the process of moving apartments when he sold his car on Sunday. Because the banks were closed, he needed a place to temporarily stash the cash.

Silvey then found a yellow travel mug and decided to store his money in it.

However, what he thought was a safe and unimposing storage location later caught the attention of his mother, Lindsay Preiss, who had just read Marie Kondo’s best-selling book “The Life Changing Magic of Tidying Up.”

Inspired by her newfound wisdom, Preiss took her time to survey their home for clutter — like many others in recent weeks — and stumbled upon a yellow travel mug that did not “spark joy” in her life.

Preiss took the Mickey Mouse mug to a local Goodwill store.

“At first I thought it was a joke or a prank or something like that,” Silvey told WSB-TV. “She thought I was upset about the mug being gone, which, I miss the mug as well, but what was inside was a little more important.”

Unfortunately, he stashed a whopping $6,500 inside the mug — and the realization filled his mother with deep regret.

“(I feel) like the worst mom in the world. I mean, I feel terrible,” Preiss said.

After realizing what happened, the family contacted the Goodwill outlet and had managers going through hours of surveillance footage in hopes of finding the mug. Eventually, they found that one employee had priced the item before disposing it on a bin to be put on shelves; nobody knows what happened with it next.

While the odds of retrieving the mug seem slim, the family hopes that whoever picked it up is kind enough to do the right thing. They offer a monetary reward.

“We would be very, very thankful if you brought it back,” Preiss said. “I’m just asking someone to please have it in your heart to do the right thing and give it back.”

Featured Images via Twitter and YouTube / WSB-TV (Right) and WSAV3 (Left)