Ridder named mob in Varulvhamn is friendly but it attacks my sm pet

I was in Varulvhamn getting Lost Pearls xp item with my SM. Ridder named mob is friendly to me, I am just moving thru the room to the hallway to the right not even going near the 'friendly' mob. It suddenly ran foward to attack my pet which was behind me. I was not attacking anything at the time. I recreated this by making sure my pet is on passive and it again, after spawn, attacked my pet. It never tried to attack me.