Oops, it doesn't look like 'call to lower us flags on memorial day' is a national day..

Other days

cuddle up

Cuddle Up Day
emoji

Emoji Day
self care

Self Care Day
stress awareness

Stress Awareness Day
ruby

Ruby Day
polyamory

Polyamory Day
bow tie

Bow Tie Day
frozen yogurt

Frozen Yogurt Day
me

Me Day
kale

Kale Day