What’s the name of this movie?

The story of dog who has a boy-owner. They live with boy´s mother who works as “nurse” at war veterans home.
Owner of house they live does not allow them to have a dog at home so the dog stays with other dogs in old house coles to their home.
Once the old house is damaged for the new building to be built and they had to take the dog somewhere else.

So it happened (I forgot how exactly) the dog was taken to another city behind mountains and quit far from the one.
The rest of the story is about the dog´s road – aim to come back home.
It took a lot lifepower to get back – he met some good animal-friens but recignized to go on to come home, he met the homeless who chained him to himself and died later.
Some teens rescued him…

The happyend was the dog comes back to the guy, his mother and stays at veterans home as the friend of all around.