(((HUGS))) to you Mooshi. It sounds wise to take Zeus to the veterinary he/she could help you to decide along with your mom as what to do next. Maybe Zeus was trying to show Titan dominance? I hope that Titan will be alright physically with the veterinary treating him. This is a terrible thing to see happen & to love your dogs like you do, I surely understand because I have had this happen with my own dogs over the years. I think back to when dogs were wild & they still have that wild in them & are still territorial & there is always the dominance that is natural but can be controlled & has to be controlled so no one gets hurt. I send good healing thoughts to you & your dogs.