conditional or dependent alerts

Greetings, I need so assistance in setting up "conditional" or "dependent" alert status on hobbit, so for example, if the firewall dies, it knows that devices X, Y and Z are "dependent" on the firewall, therefore it won't tell us about 55 things that are down, just tell us the firewall is down?

This is a major pain in the rump every time we lose a VPN tunnel and we all get 100 text messages.

Kenneth