McDonald's initially hesitated about introducing Happy Meals to all its restaurants, says the man who invented them

• McDonald's was reluctant to roll out Happy Meals to all restaurants in the 1970s, its inventor said.
• Bob Bernstein, an advertising exec, told CNN he got the idea when he saw his son eating cereal.

McDonald's executives and franchise owners were reluctant to introduce the Happy Meal to all their restaurants when they were first brought in, according to the man who invented them.

In an interview with CNN, Bob Bernstein, an advertising executive who created the Happy Meal in the late 1970s, described the struggle to convince executives of the idea to create a product aimed at attracting children to McDonald's.

"They were reluctant a little bit – they didn't immediately embrace it," he said. "It took some convincing on our part."

Bernstein was tasked with creating a concept that would appeal to younger customers as McDonald's lost ground to competitors such as Burger King, which used the "king" character to appeal to kids.

He told CNN he got the idea for the Happy Meal when he watched his son pour himself cereal and allow it to spill over the sides of the bowl each day, making him realise "kids want something to do when they eat."

Bernstein proceeded to design a box that the McDonald's golden arches as handles, as well as riddles, games, and illustrations. However, it took a year of testing before the box was rolled out across the US in 1979.

"Corporate just didn't seize it immediately," he added. "They wanted to see more testing – that was a bit unusual."

Colleen Fahey, the creative director at Frankel, the advertising agency that worked with McDonald's to turn the Happy Meal into a permanent menu item in the 1980s, told CNN the box "wasn't a very popular concept" among franchise owners either.

"The boxes were complicated. They had to find a place to store the toys," he said. "They thought it was too complex for their operations."

The Happy Meal has since become a crucial part of the McDonald's menu and has evolved over the past four decades. The company even rolled out an adult version to reported success in early October.

Data research firm Sense360 calculated in 2016 that McDonald's sells 3.2 million Happy Meals each day, generating about $10 million in revenue.