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

Other days

coffee

Coffee Day
self care

Self Care Day
blanket fort

Blanket Fort Day
cursing

Cursing Day
ride the wind

Ride The Wind Day
ormille

Ormille Day
buddy

Buddy Day
singles

Singles Day
pumpkin

Pumpkin Day
prosecco

Prosecco Day