guessing shepherd/aussie, maybe a little golden mixed in?
We had adopted a 4 month old puppy who was listed as a "Bernese Mountain Dog", so I read up about them. Um, I don't think she had a drop of Berner in her, LOL! Best guess was rottie/aussie mix. Like you, we loved her to pieces and wouldn't have traded her for the world. Your Tippy is one gorgeous sweetheart!