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

Other days

bow tie

Bow Tie Day
coffee

Coffee Day
one

One Day
self appreciation

Self Appreciation Day
frozen yogurt

Frozen Yogurt Day
prosecco

Prosecco Day
lisp

Lisp Day
aloxolt

Aloxolt Day
bounce

Bounce Day
brow

Brow Day