Oops, it doesn't look like 'Booty Pic Knee Cap day' is a national day..

Other days

pick me

Pick Me Day
lash

Lash Day
ruby

Ruby Day
kiss a brunette

Kiss A Brunette Day
pumpkin

Pumpkin Day
book

Book Day
boba

Boba Day
offer

Offer Day
reading

Reading Day
eat what you want

Eat What You Want Day