Oops, it doesn't look like 'Best Friend Ls day' is a national day..

Other days

artists

Artists Day
youth

Youth Day
coffee

Coffee Day
bow tie

Bow Tie Day
blanket fort

Blanket Fort Day
hoodie

Hoodie Day
latina equal pay

Latina Equal Pay Day
slime

Slime Day
cat girl

Cat Girl Day
pumpkin

Pumpkin Day