Oops, it doesn't look like 'mourning this day' is a national day..

Other days

bow tie

Bow Tie Day

bonang

Bonang Day

ruby

Ruby Day

cat girl

Cat Girl Day

self appreciation

Self Appreciation Day

ride the wind

Ride The Wind Day

Emoji Day

african immigrant and refugee hiv and hep awareness

African Immigrant And Refugee Hiv And Hep Awareness Day

my little pony

My Little Pony Day

blanket fort

Blanket Fort Day