Merge pull request #8739 from MrSmite/PetAI_CanAttack_bugfix

Fix a minor PetAI behavioral issue

src/server/game/Entities/Unit/Unit.cpp

@@ -12106,7 +12106,10 @@ void Unit::CombatStart(Unit* target, bool initialAggro)
         if (!target->isInCombat() && target->GetTypeId() != TYPEID_PLAYER
             && !target->ToCreature()->HasReactState(REACT_PASSIVE) && target->ToCreature()->IsAIEnabled)
         {
-            target->ToCreature()->AI()->AttackStart(this);
+            if (target->isPet())
+                target->ToCreature()->AI()->AttackedBy(this); // PetAI has special handler before AttackStart()
+            else
+                target->ToCreature()->AI()->AttackStart(this);
         }
 
         SetInCombatWith(target);