'Shark Tank': Hero 9/11 firefighter created a genius cooking product — after his death, his kids turned it into a business

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On Sunday's episode of ABC's "Shark Tank," one pitch not only moved the sharks to tears, but spurred all five Sharks to collaborate on, rather than fight over, a deal.

Walking into the Tank were three siblings from Long Island, New York: Kaley (24), Christian (20) and Keira Young (15) with their product, Cup Board Pro. The cutting board was created by their late father, Keith — a New York firefighter, firehouse chef and two-time "Chopped" star who died of cancer related to his time doing cleanup at Ground Zero in lower Manhattan after September 11, 2001, according to the Youngs.

The Cup Board Pro is a bamboo cutting board with an attachable tray so food scraps can be brushed into it, and it has strategically placed grooves for meat or other juices to run into the tray, all for easy cleanup.

While the sharks were impressed with the quality and effectiveness of the cutting board, the entrepreneurs' personal story made an even bigger impact. For their pitch, the Youngs, who were seeking $100,000 for a 10 percent stake in their business, played a video of their father demonstrating the product. Keith had made the video for his "Shark Tank" audition tape before he died in March.

And that wasn't the only tragedy the family had endured.

Kaley told the investors that her father created the Cup Board Pro when she was in high school in 2010, but as he received the product's first prototypes, their mother, Beth King, was diagnosed with breast cancer. The business took a backseat and King died at age 47 in 2012.

After her death, Keith was selected to be on Food Network's "Chopped," and went on to win — twice. That experience gave him the confidence to resume work on the Cup Board Pro, Kaley said.

In December, Keith had 2,000 Cup Board Pros made to launch his business. But just as he received the final product, Keith was diagnosed with a 9/11-related cancer. He died in March.

But the siblings were not willing to let their father's passion die with him. They took his inventory, launched a website and began selling the product, selling 300 boards by the taping of the show.

"It was our dad's dream to have the Cup Board Pro in kitchens all over the world," the siblings say on the business's website. "We feel honored to be able to continue his legacy and to share a little bit of Keith Young and the Cup Board Pro with you all."

While it may all seem overwhelming, the Youngs say they can handle it.

"Honestly, it's kind of hard to overwhelm the three of us because of just the amount of stress you go through seeing your loved ones sick. We are only able to be here because of how strong our parents were," Kaley told the Sharks.

Daymond John, who was crying by the end of the pitch, asked the Youngs to step out of the Tank, and the investors decided to work together. Lori Greiner, who also teared up, said she could easily sell all of the Youngs' current inventory on QVC, while Kevin O'Leary was impressed but said they needed to bring down the $12.50 it costs to make the Cup Board Pro (the retail price was $40, the Youngs said on the show). After their quick huddle, the Sharks called the Young siblings back into the tank.

"Your story is amazing," Mark Cuban said. "Obviously, you have a million reasons to be proud. And your father will live on forever through each of you and this product. But rather than us fight it all out, we decided to work together."

John told the stunned siblings that such five-Shark collaboration is a rarity. "In fact, it pretty well never happens," said O'Leary.

The five sharks offered the Youngs $100,000 for 20 percent, with each shark contributing $20,000. Any profits the sharks earn from their investment will be given to a charity helping firemen who have become sick after 9/11.

The Youngs accepted the deal.

"This is the beauty of entrepreneurship," Cuban says. "They're going to be able to support themselves. This is going to be a product that's going to go on forever."

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Disclosure: CNBC owns the exclusive off-network cable rights to "Shark Tank."

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