At 3 months of age, surgery to dock her tail would be comparable to an amputation, would be painful and require recovery. Why not just leave her tail? So many yorkies especially in Canada and Europe have full tails, she would have lots of company.
My parti boy has a full tail and I love it! He carries his tail nicely, it's so cute waving back and forth.
ETA: sorry, just now read Jodi's post to you....didn't mean to repeat the same.