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

Other days

boyfriend

Boyfriend Day
nae nae

Nae Nae Day
frozen yogurt

Frozen Yogurt Day
lumpy rug

Lumpy Rug Day
kiss a ginger

Kiss A Ginger Day
carpenters

Carpenters Day
tulip

Tulip Day
hot chocolate

Hot Chocolate Day
healing

Healing Day
hoodie

Hoodie Day