When Americans latch onto a fast-food trend, it can be hard for everyone to keep up. 

Nearly three years after Popeyes kicked off the chicken sandwich wars, McDonald’s found a buzzy, viral menu item of its own: the limited-edition (and now sold out) Cactus Plant Flea Market Box combo meal, also known as the adult Happy Meal. The meals were incredibly successful after debuting earlier this month, with toys currently going for exorbitant amounts on the resale market.

According to recent CivicScience data, 5% of adults got to give these a try and enjoyed them – with nearly five times as many adults still interested in trying them in the future (n=2,961). Although it was marketed as a limited engagement, McDonald’s certainly has strong demand to bring back the adult Happy Meal.

Younger Americans are overwhelmingly more likely to have tried and liked the adult Happy Meals – with Gen Z adults twice as likely as the next closest age group (25-34) to fit the bill. While Gen Z also well outpaces the Gen Pop in intention to try, nearly a quarter or more of all adults under 54 are also interested in trying it. Even 17% of the over-55 set are interested.

While parental status isn’t as predictive for determining who has already tried adult Happy Meals, childless adults are the most interested in giving them a try down the road. So those with less proximity to present-day Happy Meals for kids seem to have more interest across the board for the adult offering – which might also explain the one-fifth of grandparents with interest.

Ultimately, the nostalgic draw is extremely powerful in determining consumer interest in adult Happy Meals. More than one-third of adults who got Happy Meals ‘very often’ as a child tried and liked the adult offering – which drastically outnumbers the Gen Pop’s rate. All adults who got Happy Meals to some degree outpace the Gen Pop in interest to try in the future, but even 13% of adults who never got them as children are willing to give the grown-up version a try.

McDonald’s is also pursuing its second nostalgic revival this month with the return of Halloween Happy Meals, also known as Boo Buckets. Available for the first time since 2016, the buckets should be similarly buzzy as the adult Happy Meals. According to CivicScience data, more than one-quarter of adults are at least somewhat likely to purchase one, and a staggering two-thirds of Gen Z adults surveyed said the same (n=3,405).

Although McDonald’s may truly be approaching the adult Happy Meal as a one-off limited engagement, there’s plenty of sustained demand for this sort of nostalgia appeal should they choose to revive the promotion. The younger fans and adults with childhood connections to Happy Meals will be first in line, but quite a few grandparents won’t be far behind.