Oops, it doesn't look like 'booty day' is a national day..

Other days

lisp

Lisp Day
mean girls

Mean Girls Day
girl friend

Girl Friend Day
frozen yogurt

Frozen Yogurt Day
hiv awareness

Hiv Awareness Day
camera

Camera Day
stress awareness

Stress Awareness Day
kale

Kale Day
tulip

Tulip Day
cat girl

Cat Girl Day