Oops, it doesn't look like 'irrelevant old fucks day' is a national day..

Other days

youth

Youth Day

donate your hair

Donate Your Hair Day

artists

Artists Day

comfy

Comfy Day

girl friend

Girl Friend Day

lumpy rug

Lumpy Rug Day

embarrass your best friend

Embarrass Your Best Friend Day

Me Day

prosecco

Prosecco Day

eat what you want

Eat What You Want Day