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

Other days

Chocolate Milkshake Day

Lost Sock Memorial Day

Tell A Fairytale Day

Nae Nae Day

Buddy Day

African Immigrant And Refugee Hiv And Hep Awareness Day

Raise Awerness Of Zeus Day

Ponytail Day

Lumpy Rug Day

Slime Day