[Alfredo looks up in the middle of chewing a gummy worm.

Putting the rest of his treats aside, he accepts the string with another smile.]

Thank you, Della! Now, we just need to make the right-size hole for the strings, then tie them in knots inside...

[He's speaking this out loud mostly for his own benefit; it's easier for him to catch his own logic mistakes if he's hearing then rather than thinking them.]