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

Other days

african immigrant and refugee hiv and hep awareness

African Immigrant And Refugee Hiv And Hep Awareness Day
bow tie

Bow Tie Day
hot chocolate

Hot Chocolate Day
gum

Gum Day
self appreciation

Self Appreciation Day
stress awareness

Stress Awareness Day
azonto is acceptable

Azonto Is Acceptable Day
promposal

Promposal Day
lash

Lash Day
frozen yogurt

Frozen Yogurt Day