The initial idea was nothing more than a one-minute video for the Children’s Hospital of Wisconsin website, Facebook page and social media, playing off the $85 rocks sold by Nordstrom this holiday season and reminding people that a donation to the hospital might be a more worthwhile way to spend money.

It got a bit more involved from there.

But, even then, no one expected the result: more than $125,000 in donations, including $50,000 from Nordstrom, as of Friday morning to the Children’s Hospital of Wisconsin Foundation.

The money stemmed from an ad-hoc campaign called “Rocks for a Reason.”

The marketing and communication types at Children’s Hospital at first just wanted to draw attention to a good cause, and they had the perfect person for the part — Dave Margolis, a physician who has been called “the oldest and biggest kid at Children’s.”

Margolis was open to the idea, but only if Children’s Hospital sent an actual rock for each $85 donation.

“It was never our idea to send rocks,” said Andy Brodzeller, a spokesman for Children’s Hospital. “It was his idea. He said, ‘If you want me to do this, we are going to send out rocks.’”

Stars can be demanding, and Margolis, who is also a professor at the Medical College of Wisconsin, was from central casting for the role.

He did his residency and fellowship at Children’s Hospital and never left. He is a physician who lets his patients paint his hair in the colors of the Milwaukee Bucks if they make the playoffs — someone who is quick to laugh and who puts a value on having fun.

Both may be survival skills when you specialize in pediatric hematology and oncology, a field that has seen impressive advances but that still brings its share of heartache.

Margolis’s 58-second video was a mix of incredulity about the retail fad of rocks selling for $85 and a low-key pitch:

“A donation of $85 can go a long way in helping a kid be a kid or even helping a kid get better. So I’ve got a better idea. Instead of donating $85 to a major retailer for a rock, send us $85 and I will be happy to send you a rock from the beautiful shores of Lake Michigan.”

The video was shared by more than 5,000 people on Children’s Hospital’s Facebook page and was viewed by more than 500,000 people.

It also led stories by Today.com and the BBC.

Nordstrom wasn’t named in the video — Margolis said he didn’t want to single out the department store chain — but the company apparently took note.

The company's unexpected call to the foundation wasn’t exactly, “May I please speak to someone about giving $50,000 to the hospital?” But it was a bit like that.

“It’s unreal,” Margolis said.

Children’s Hospital and its foundation now have people sending off rocks, with a note card attached by a rubber band, in 5-by-7-inch padded envelopes.

The note card has a picture of the hospital on one side and a pun on the other.

“Thank you,” the card reads. “Your donation could not serve a boulder purpose: the very best care for kids.”

Margolis signs every card, usually with, “You rock. Dr. Dave.” He writes personal notes to friends, former patients and others whose name he recognizes.

He signed about 500 of them last weekend, typically working 15 to 20 minutes at time, starting Saturday morning and finishing before the Packers game.

“I’m looking at the next stack I get to sign,” he said.

The stack could continue to grow: Tuesday and Wednesday were the biggest days so far for donations.

“None of us — particularly Dave — thought this would be the result,” Brodzeller said.

Margolis doesn’t dispute that. But sometimes events come together nicely.

“Right time. Right place. Right cause,” he said.

More information, including how to donate to the "Rocks for a Reason" campaign, is available at http://www.chw.org/giving-and-volunteers/rocks-for-a-reason