Oops, it doesn't look like 'use a house phone day' is a national day..

Other days

ponytail

Ponytail Day
cuddle up

Cuddle Up Day
ruby

Ruby Day
hoodie

Hoodie Day
china

China Day
gum

Gum Day
carpenters

Carpenters Day
lumpy rug

Lumpy Rug Day
blanket fort

Blanket Fort Day
fiancee

Fiancee Day