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

Other days

offer

Offer Day
bow tie

Bow Tie Day
tell a fairytale

Tell A Fairytale Day
frozen yogurt

Frozen Yogurt Day
comfy

Comfy Day
ruby

Ruby Day
hot chocolate

Hot Chocolate Day
boba

Boba Day
boy friend

Boy Friend Day
prosecco

Prosecco Day