Boy, 15, now teen millionaire after 'randomly' inventing hit game when he was 7

A teenager has become a millionaireafter inventing a best-selling card game when he was just seven years old.

Alex Butler, now 15, sold the popular game Taco vs. Burrito, which he developed with his parents Leslie Pierson and Mark Butler, to PlayMonster last month for an undisclosed amount.

"It was never something that I've been attached to or anything," the teenager said. 'It's not super important to me. I just kind of wanted to get the most money out of it." It comes after thousands of Brits to get shock letter from HMRC after drastic new tax rule comes into force.

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The game - which asks players to compete to make the priciest meal - sold for an unspecified amount. However, the youngster has revealed how he and his parents are investing the money, and about his plans to "buy a Lambo", the Seattle Times reports.

Alex - who said he didn't even like the Mexican dishes at the time - said the idea for the game popped into his head "randomly".

He and his family often played card games, which inspired him to develop his own. Alex would regularly test out prototypes for the game with his parents at their local coffee shop.

En route home, he would often develop new ideas to add, according to his mum, Leslie Pierson, who describes herself as a "serial entrepreneur".

He soon introduced the game to pals and due to its popularity Leslie started a fundraiser online to cover startup costs.

After the first day, Alex was left stunned when his mum told him they'd raised $1,000 (£745).

"He lost it, mind blown," Pierson said.

The fundraiser, and a promotion event at Comic Con, eventually raised $25,000 (£18,624) and Alex's father decided to set up a company, Hot Taco Inc. Alex owns the majority share.

Then came choosing a manufacturer. Pierson said they found one who "treated Alex like an adult" and then spent over $25,000 on the products, which were then put on Amazon.

By the end of year one, they'd made just shy of $1.1million (£819,285). Since then, 1.5million copies of Alex's card game have been sold.

They realised their operation was too small to cater to the huge demand, and started considering a buyout. Eventually they settled on PlayMonster, with Alex having a key role in the decision making.

Jonathan Berkowitz, CEO of PlayMonster, told the Seattle Times he loved the game because the "characters are amazing."

"It's always fun when kids can beat their parents in a game, but the parents can still truly enjoy playing," he said.