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

Other days

cuddle up

Cuddle Up Day
brow

Brow Day
one

One Day
nae nae

Nae Nae Day
tell ur crush you like them

Tell Ur Crush You Like Them Day
ride the wind

Ride The Wind Day
singles

Singles Day
me

Me Day
bounce

Bounce Day
buddy

Buddy Day