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

Other days

ride the wind

Ride The Wind Day
offer

Offer Day
buddy

Buddy Day
self care

Self Care Day
bow tie

Bow Tie Day
lumpy rug

Lumpy Rug Day
boy friend

Boy Friend Day
hoodie

Hoodie Day
china

China Day
fiancee

Fiancee Day