What’s better than a Happy Meal with one toy? A Happy Meal with two toys, of course! This holiday season, McDonald’s is handing their customers double the fun—but it isn’t necessarily for the reason you’d think.

McDonald’s embraces the gift-giving spirit by introducing a limited-time Happy Meal that includes two toys. The company announced that it would sell “Pet Simulator Happy Meals” with two toys at participating restaurants nationwide starting Tuesday.

If you order a Happy Meal at McDonald’s soon, though, you may notice a difference: two toys. It may seem like a stroke of good luck or a mistake, but it’s neither. Here’s the story behind McDonald’s double toy Happy Meals.

The truth is, no one can really agree on who first invented the iconic McDonald's Happy Meal. Here's why the history behind it is so complicated.