OH, GROW UP: Some smartphone-carrying millennials and Gen Zers are so used to texting upon arrival that the sound of a ringing doorbell freaks them out; ‘it’s terrifying.’

“Doorbells are just so sudden. It’s terrifying,” says Tiffany Zhong, 20, the founder of Zebra Intelligence, which helps companies conduct custom research and gather insights on people born in the past two decades.

There’s no published research about doorbell phobia, but it’s a real thing. In a poll by a Twitter user earlier this month that got more than 11,000 votes, 54% of respondents said “doorbells are scary weird.”

Some millennials and Gen Zers say they won’t even consider answering a ring at the door until they’ve checked the security camera.

The doorbell freak-out reflects the ascendance of mediated communication, which means people interacting through technological devices rather than directly. It’s not so much about screen time versus face time as it is a merger of the two.

What do these adult-sized children do when faced with simple household chores like a clogged toilet or a lamp in need of new wiring?