We have transferred all of Calvin's footie pajamas to a bin in the coal room. Not only has it been abnormally warm (just what I asked for, thanks) so that sleeping in fleece from top to bottom is unnecessary, but more importantly they give him a "knee-bend."
From what I gather, a knee-bend is the vilest of nighttime discomforts chiefly inflicted by footie jammas.
When Calvin is very sincere about something, regular English is rarely accurate enough to convey his message. His own words are then used instead.
Sometimes his meaning isn't understood without a demonstration.
But in the end he usually gets his point across.