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

Other days

martini

Martini Day
book

Book Day
lash

Lash Day
kiss a ginger

Kiss A Ginger Day
one

One Day
lisp

Lisp Day
bow tie

Bow Tie Day
brow

Brow Day
singles

Singles Day
kiss a brunette

Kiss A Brunette Day