If you choose The Needs of the Many as your wish in the Tattered Spire, then all those who had died in it's creation would be brought back to life. If you choose The Needs of the Few, your dog and family will be brought back to life. The final choice, the Needs of the One gives the hero one million gold pieces. The only other way to get your four legged friend back is in the Knothole Isle DLC. The hero may trade the soul of a citizen of knothole island in a strange shrine for the soul of their deceased dog. All info is taken from