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

Other days

youth

Youth Day
one

One Day
prosecco

Prosecco Day
nae nae

Nae Nae Day
eat what you want

Eat What You Want Day
self care

Self Care Day
first love

First Love Day
tulip

Tulip Day
healing

Healing Day
china

China Day