He was just over a year old. Being a semi-feral cat is a hard life; that's the second one out of the pride that we've lost.
He was also the first one to slowly move into being approachable, though once his big brother Tawny realized That Was A Thing, he immediately took over as Speaker to Tall Ones. Spock and Kirk, I tell you.
We'll keep an eye on the rest of them. It's really well past time to round them up for vetting.