diapers

"Bill reveals the stunning engineering underlying the design of a diaper. He describes the five layers of a diaper, including the superabsorbent polymer in the diaper's core. He illustrates the action of this polymer with a stunning demonstration using a single bead of polymer: it soaks up enough water to grow from a diameter of 4 mm to nearly a half inch."

Either way, too shy to find out the answer.

There are hedgehog diapers now? Adorable.