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

Other days

coffee

Coffee Day
first love

First Love Day
pick me

Pick Me Day
camera

Camera Day
martini

Martini Day
cuddle up

Cuddle Up Day
artists

Artists Day
believe

Believe Day
ponytail

Ponytail Day
lumpy rug

Lumpy Rug Day