How is the director shooting this scene? (Evil tv series)

Those of you who watch the show will know what I’m talking about. One of the main protagonist of the show is a mother to 5 (4?) children. They have a recurring theme when all of the children are on camera.

They start off by having a normal conversation. Then they gradually start to talk over eache other as their voices get louder and louder. They also start to talk a hundred mile per hour.

The whole spectacle is like nails on the chalkboard. That said, I’m quit impressed by the director’s and actor’s ability to evoke that kind of reaction.

So my question is, is it scripted? Or do they improve? And if it’s scripted, how do they get the timing right?

I apologize, I tried to link an example but could not find one.

It’s a great bit of business, and from here:

The Kings told TV Guide they “adore” the young actresses who bring Kristen’s daughters to life, whose nonstop talking over each other is inspired by the creators’ own lives. “I’m from a family of seven kids,” Robert explained. “It was usually three or four people talking on top of each other, driving our parents crazy, but there’s a great energy that comes with that.” To keep the girls’ dialogue feeling real, their lines are grouped together in the scripts for the actresses to split up and riff on as they go. “I would say two thirds of the lines they’re speaking are scripted and one third are ad libs on their part,” he added.

Wow, that’s interesting. Thanks.