Oops, it doesn't look like 'pee the bed for dream day' is a national day..

Other days

gum

Gum Day
cursing

Cursing Day
nae nae

Nae Nae Day
girl friend

Girl Friend Day
chocolate milkshake

Chocolate Milkshake Day
youth

Youth Day
lisp

Lisp Day
china

China Day
tulip

Tulip Day
cat girl

Cat Girl Day