What does a Yak have to do with hygiene?

Eric Carle

This "Yickity-Yak" who is "sniggildy-snaggildy" and covered with "shiggildy-shag", brought my prompting home. Leyla is now determined to toughen up, not fuss and be diligent about her daily hair brushing - lest she look like him.

Thank you, Yak.