Oops, it doesn't look like 'convention in two differrent states same day' is a national day..

Other days

hoodie

Hoodie Day
boy friend

Boy Friend Day
my little pony

My Little Pony Day
stress awareness

Stress Awareness Day
martini

Martini Day
hiv awareness

Hiv Awareness Day
self care

Self Care Day
ruby

Ruby Day
unicorn

Unicorn Day
bubble bath

Bubble Bath Day