// Remove this player from the sick players
 public void UnregisterHealedPlayer(MobSickness mobSickness)
 {
     lock (sickPlayers)
     {
         if (!sickPlayers.Contains(mobSickness))
         {
             sickPlayers.Remove(mobSickness);
         }
     }
 }
 // Add this player as a sick player
 public void RegisterSickPlayer(MobSickness mobSickness)
 {
     lock (sickPlayers)
     {
         if (!sickPlayers.Contains(mobSickness))
         {
             sickPlayers.Add(mobSickness);
         }
     }
 }