My wife was commenting that our dog would have turned 32 yesterday. She knew because her iPhone notified her, thanks to having set the birthday in her contacts and enabling the birthday calendar. That happens to me too, for pets and people. It’s been a problem for years.
And I’m surprised it’s not something that has come up yet on Apple’s radar. Surely higher-ups at Apple get birthday notifications for deceased loved ones too. I’m curious why it hasn’t been addressed. Especially considering that the solution seems pretty straightforward: add a death field to the contacts database.