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

Other days

self care

Self Care Day
boba

Boba Day
coffee

Coffee Day
bow tie

Bow Tie Day
kiss a brunette

Kiss A Brunette Day
prosecco

Prosecco Day
kale

Kale Day
eat what you want

Eat What You Want Day
gum

Gum Day
mean girls

Mean Girls Day