You can add the same object to different families depending on what tasks you need to do with each family.
For example you have these objects:
FriendlyTank
FriendlyTrooper
EnemyTank
EnemyTrooper
You can create Friendlies family (with FriendlyTank + FriendlyTrooper) and Enemies family (with EnemyTank + EnemyTrooper).
Assign turret behavior on both families and set target to each other.
You can also create Vehicles family (with FriendlyTank + EnemyTank) and People family (with FriendlyTrooper + EnemyTrooper).
And then define some vehicle-specific events or behaviors for Vehicles family, and some different events for People. For example, all vehicles will explode when destroyed and all people will leave a blood spot.