So you’re having a party in your garage, and your kid’s friend shows up with a gun. He’s pissed about something, and since he’s a kid, he’s fuckin stupid and starts shooting. Your cat bounces; your dog attacks.
This is Zero, and that’s what he did. He saw his family being hurt, he saw the asshole hurting them, and he jumped in with no hesitation. He earned a bullet for it. Then, more shots, and Zero jumps back in, only to get shot 2 more times. 3 people get sent to the hospital with gun shot wounds. The dog dies in the yard.
My guess is that if there is a heaven, there are definitely dogs in it.