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

Other days

hoodie

Hoodie Day
youth

Youth Day
kiss a brunette

Kiss A Brunette Day
coffee

Coffee Day
self care

Self Care Day
kiss a ginger

Kiss A Ginger Day
polyamory

Polyamory Day
book

Book Day
ruby

Ruby Day
lost sock memorial

Lost Sock Memorial Day