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

Other days

cuddle up

Cuddle Up Day
book

Book Day
boy friend

Boy Friend Day
lumpy rug

Lumpy Rug Day
stud

Stud Day
nae nae

Nae Nae Day
bubble bath

Bubble Bath Day
buddy

Buddy Day
lost sock memorial

Lost Sock Memorial Day
ruby

Ruby Day