As a player you can dodge and strafe to avoid dmg from aoe attacks, however the pets don’t do this and die a horrible fast death because of it.
To help them survive at least bit longer I would give them a 40% dmg reduction on aoe attacks. This seems a lot, but that is roughly the % dmg you mostly can avoid by just moving arround, and if you are realy looking at where you run you as a player can even avoid more.