It’s bedtime.

Phineas: “I want Carrie!”
Me: “No. You guys have done all your Carrie-ing for the day. Now it’s time for bed.”
Ezra: “Yeah, now we have to do the rest of our Nate-ing!”

Ezra thinks a bit.

Ezra: “‘Nate-ing’ and ‘Native Americans’ are easy to mix up.”