Ethan Sanborn is an 8-year-old entrepreneur who just landed a five-figure investment on ABC's "Shark Tank."

Sanborn and his father, David, pitched their kid-friendly coffee business, Kiid Coffee, on Friday's episode of the show. They generated serious investor interest, despite having a barely year-old business and an elementary school-aged co-founder.

Kiid Coffee launched in April 2024, though Ethan was interested in business long before that, according to his father. He likely gets that from his dad, as David has started a handful of past businesses himself, including a pet-food flavoring business he sold in 2020, according to his LinkedIn profile.

David says his son pitched him on several businesses in recent years, from selling lemonade to Pokémon cards. After trying some sips of his David's coffee one day, Ethan came up with the idea of a version made for kids. David wasn't immediately sold on the idea, picturing grown ups turned off at the thought of highly caffeinated children.

"I was like, 'Parents are going to go crazy. That's a terrible idea,'" David tells CNBC Make It.

"'If I like it, somebody else is going to like it,'" Ethan said, according to his father, and that logic proved tough to refute. David suggested Ethan ask around at school, while he looked at studies of children's interest in coffee. When they both got positive feedback, the two of them decided to give the idea a shot.

Ethan and David tried more than 100 different recipes — varying the types of decaffeinated coffee, flavoring, and added vitamins — until they got a combination that felt right right. The test batches were made in their home kitchen and handed out in plastic baggies to interested neighbors, though Ethan and his younger brother remained the primary taste testers.

"Number one thing the parents have to ask is, 'Will my kids actually eat or drink this?'" David says.

Kiid Coffee has a "negligible" amount of caffeine, according to the website. It contains prebiotic fiber and minerals like calcium and iron. The added nutrients were an important point for David, especially if Ethan wanted to drink the coffee "every morning."

In 2024, the product brought in about $150,000, according to documents reviewed by CNBC Make It, and is re-investing any profits, David says. He currently has another full-time job and relies on three part-time employees to help handle the business's needs.

Choosing the Shark with 'massive' relevant experience

The "Shark Tank" judges raised concerns that the endeavor was too young to warrant an investment. "The problem with this business is that there's just so much to do," Mark Cuban said.

Initially he declined to invest. Cuban's interest quickly reappeared, however, when he heard that the product is sold in a number of coffee shops, both by the bag and as individual cups.

Cuban liked the idea of "using coffee shops as leverage to sell," rather than relying solely on online sales. He wasn't the only one.

Cuban and Lori Greiner made a joint offer of $50,000 for a 20% stake in the business. After revising initial offers, Daniel Lubetzky, the founder of Kind Snacks, offered the pair $50,000 for 20%, but with the opportunity to refund 5% of equity if David joins the business full-time. O'Leary also revised his offer to $50,000 for 15%, down from 30%.

The pair accepted Lubetzky's offer. David confirmed to CNBC Make It that the deal went through after filming.

"He's just, overall, a great human being," David says of Lubetzky, and why they chose to work with him. "And then, the fact that he has massive consumer products, food experiences is very valuable [and] important as we move forward."

Ethan remains involved with the business' social media marketing, particularly making videos for Kiid Coffee's TikTok page, which has nearly 10,000 followers. He and David take roughly 30 minutes per day to go through customer feedback and brainstorm ideas.

Still, Ethan isn't missing out on being a kid, according to his dad.

"Ethan is actually very interested in the business," David says. "But, at the same time … [my children] have the freedom to be like, 'I need to go out and play for a little bit.'"

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