Thank you everyone.
I will post their pictures in the next few days.
Kobe is very friendly to us at home, very loving dog.
He is so gentle and never aggressive toward us.
Even during meal time I can put my hand in his bowl.
Always likes a cuddle, fetches ball and play chase with Bailey.
Outside our house is a different story. He is always on guard.
He lunges at other dogs when they are too close so I always keep our distance. Once a dog approached us and Kobe when ballistic and I blocked him with my leg. He ripped my jeans but fortunately only scratched my leg.
I don't think he realised he bit me. He panicked.
When he is anxious around other dogs he won't even accept treats.
Once I met a lady in a park that used to breed Shelties and she said she has never seen a Sheltie as aggressive as Kobe.

Somehow Kobe was very friendly to her Sheltie.
I wish I knew what happened to him in the first 8 months of his life.
I read a lot of books and talked to Sheltie breeders before we got him. Aggressive Sheltie was the last thing we worried about. We were concerned about getting a dog that was too timid.
One big mistake we did was to get a dog without seeing it and the parents in person. We took their words as they are a reputable breeder 3000 miles away from where we live. We emphasizied that a good temperament and good health were the most important things. Colour and size were not important.
From the first time I took him out I knew he was not well behave. I called the breeder and they said give him time to adjust. Also having him sterilized should help so Kobe had it 2 weeks later but didn't help. I am still not sure if they knew about his behaviour issues. Being a show dog amongst many others that they had, Kobe wouldn't have been walked in a park. They simply wouldn't have time.
I would have returned him straight away if I knew that it was going to be this difficult to change him. Now he is part of the family we couldn't let him go.
We live in hope.