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

Other days

stress awareness

Stress Awareness Day
believe

Believe Day
buddy

Buddy Day
african immigrant and refugee hiv and hep awareness

African Immigrant And Refugee Hiv And Hep Awareness Day
boyfriend

Boyfriend Day
china

China Day
pampering

Pampering Day
ruby

Ruby Day
my little pony

My Little Pony Day
bubble bath

Bubble Bath Day