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

Other days

singles

Singles Day
ruby

Ruby Day
nae nae

Nae Nae Day
bow tie

Bow Tie Day
embarrass your best friend

Embarrass Your Best Friend Day
blanket fort

Blanket Fort Day
pampering

Pampering Day
brow

Brow Day
unicorn

Unicorn Day
comfy

Comfy Day