Oops, it doesn't look like 'liam gain tweet day' is a national day..

Other days

polyamory

Polyamory Day
ruby

Ruby Day
first love

First Love Day
martini

Martini Day
stress awareness

Stress Awareness Day
pumpkin

Pumpkin Day
boba

Boba Day
buddy

Buddy Day
blanket fort

Blanket Fort Day
reading

Reading Day