On the TV show "How I Met Your Mother," the character of Barney (Neil Patrick Harris) was a germophobe. In one episode, everybody had the flu except Barney, and he went around with his hand sanitizer telling everybody, "Please maintain a five foot perimeter." It goes without saying that he got sick, and was the sickest of everyone.
The five foot perimeter has become one of those inside jokes, a/k/a family shorthand.
Here are Tokyo and Zing maintaining the five foot perimeter :)
Look..... they each have their own special towel. Awwwwwwwwwwwwwwww!
xo xo xo