If Uncle Loony wants to leave his entire estate to his parakeet, that's his call. His relatives and the state should have nothing to say about it.
Animals don't have property rights, so unless the state does actively allow it, it's simply not possible to leave your estate to a pet.
I can hardly wait until some old arrogant geezer trains his parrot to contest the parakeet's intestate claims for permanent care.
I wonder what intestate laws might insue from this provision, though hardly a new provision in other states. Indiana, I believe also provides for pet trusts.
So in the pecking order, by default, if the wife receives 50%, 1st direct children/siblings share in the next 25%, and then the 2nd tier relatives in 15%, would the Cocker Spaniel inherit more than the Siamese Cat?,...the parakeet?,...the goldfish?,...or that baby elephant out back?