"Oh, what is it?" I asked.
"Some guy is "light in his shoes!" the boy announced, innocently.
Uh, oh. "Oh! You mean someone is "light on his feet!" I replied, thinking as quickly as I could.
I could tell by the boy's expression that this did not quite fit what he had in mind, but he opted not to pursue it, for which I am grateful. I had no particular desire to touch that one... not even with a ten-foot pole.