Oops, it doesn't look like 'delete your thorn day' is a national day..

Other days

stud

Stud Day
unicorn

Unicorn Day
ruby

Ruby Day
china

China Day
pick me

Pick Me Day
chocolate milkshake

Chocolate Milkshake Day
artists

Artists Day
cuddle up

Cuddle Up Day
lisp

Lisp Day
boy friend

Boy Friend Day