Crossword theme help

My dad asked me to help him understand last Sunday’s crossword puzzle theme.

The name of the theme was “the long and short of it”

The answers all replaced “**L” with “ILL” such as…

Electric Eels -> Electric Ills (eel -> ill)
North Carolina Tar Heels -> North Carolina Tar Hills (eel -> ill)
Happy Meals -> Happy Mills (eal -> ill)
Banana Peel -> Banana Pill (eel -> ill)
Let’s Make a Deal -> Let’s Make a Dill (eal -> ill)
Cold Hard Steel -> Cold Hard Still (eel -> ill)
Hamster Wheels -> Hamster Wills (heel -> ill)

Not sure how the last one fits but that’s the answer. I looked it up.

What does that replacement scheme have to do with the theme’s name?

Long and short vowels – it’s two pronunciations of the “e” sound, one long (“ee”) and one short (“ih” or “eh”).

Thanks. That wheel get him off my back about it. :wink: