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

Other days

slime

Slime Day
brow

Brow Day
hot chocolate

Hot Chocolate Day
frozen yogurt

Frozen Yogurt Day
hannah

Hannah Day
kale

Kale Day
self care

Self Care Day
ponytail

Ponytail Day
nae nae

Nae Nae Day
law

Law Day