They say a chinchilla's health is directly correlated with how healthy their teeth are. Therefore, it was established on this day because of the pun with the expression "good teeth"!
The pun:
Good teeth → ii ha → i(1) i(1) ha(8)
The 18th of January is
Beloved Chinchilla Day!
There is
no way
I'm giving these to you!This is the last thing I get to look forward to!