Oops, it doesn't look like 'on their day' is a national day..

Other days

african immigrant and refugee hiv and hep awareness

African Immigrant And Refugee Hiv And Hep Awareness Day
me

Me Day
promposal

Promposal Day
my little pony

My Little Pony Day
lumpy rug

Lumpy Rug Day
donate your hair

Donate Your Hair Day
blanket fort

Blanket Fort Day
hoodie

Hoodie Day
hiv awareness

Hiv Awareness Day
prosecco

Prosecco Day