Oh, Molly, what a beauty!!! That and everything else nice there is to say about such a precious little girl. But before we get too carried away let's defer to the eleven-year-old Sheltie named Sandi for just a bit. Love and lots of it is the key to a successful joint venture for Sandi and Molly. If I may, I will relate my own experience in this realm. One year ago we came across a twelve week old male Pitt/Boxer mix that was abandoned on a rural road in our area and brought him home to our two girls: Annie, an eleven year old miniature greyhound and Sweet Pea a nine year old Lab mix. Annie has always been very outgoing and accepted the rambunctious puppy immediately. Sweet Pea, who had been our baby for nine years, would not acknowledge the puppy. She didn't offer to hurt him but she would totally avoid him and seemed to pretend that he did not exist. Due to the stress of this situation, Sweet Pea became physically ill and began to have trouble with her vision in one eye and we took her to the vet to be on the safe side. We were almost ready to find the puppy a new home in order to save Sweet Pea but we knew from previous experiences just how powerful love can be in some cases. So, we made a point of dispensing love in large doses everyday to assure Sweet Pea that she was as important and as loved as ever. We also let her know that we fully accepted the puppy. We would often cuddle with her and the puppy at the same time but always allowing her the option to withdraw if she so chose. After about two weeks of this intensive love fest, our sweet Sweet Pea approached the puppy and gave him her blessing. From that moment on the three canines have been true siblings that run, wrestle and have lots of fun everyday. By the way, that twelve week old puppy named Tyson is now at eighty (80) pounds and loves his sisters like a good brother should. I fully believe that with Love, all things are possible. Please allow Sandi the time and space she needs to come to terms with the idea of Molly as a little sister. They will both love you for it later and they will love and enjoy each other as a result of the right efforts now. Best of luck for a happy and joyous family. I hope your situation turns out as wonderfully as ours has. Love Is The Key That Unlocks Most Hearts.