OK but sir this is a Wendys and there are 12 people on their lunch break lined up behind you. Please collect your child from the floor, shut them up and move along.
That's not incompatible. Of course you can't do that in the middle of the floor.
> Probably not fixable in the moment.
Precisely
Sometimes (often) that something is merely a transient disconnect between their lizard brain reward/fear-centers and their rational cortex. There's not much to be done other than wait for the jello computer to stabilize itself.
This is surprisingly applicable to humans of all ages.
But yes, waiting, connecting with them, and helping them to calm, and process the emotions.