Oops, it doesn't look like 'flag will be flown at half mast throughout india on the day' is a national day..

Other days

Kiss A Brunette Day

Pumpkin Day

Believe Day

Polyamory Day

Fiancee Day

Unicorn Day

Embarrass Your Best Friend Day

Blanket Fort Day

Lumpy Rug Day

Chocolate Milkshake Day