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

Other days

ponytail

Ponytail Day
boba

Boba Day
latina equal pay

Latina Equal Pay Day
hannah

Hannah Day
blanket fort

Blanket Fort Day
kale

Kale Day
hot chocolate

Hot Chocolate Day
tulip

Tulip Day
lisp

Lisp Day
boy friend

Boy Friend Day