My dogs answer to about anything: Isabella - Bella - Bella Boo - Boo Boo - Baby Boo ...
They don't much mind as long as I'm happy when I call them and they get loved on when they get there
If you think he really identifies with his current name, use it and his new name at the same time, then just his new name after a while. They're really a lot more flexible than we give them credit for
BUT, he's your dog, so name him what you want. If you like Sugar, then Sugar it is. You should hear what I called my hubby at times, and it didn't decrease his manliness any
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