Congratulations & welcome to YT!
Thank you so much for giving this little girl a loving home. Sunny sounds so precious and loved already. We would love to see some pictures!
No, you are definitely not worrying too much. Many of these little yorkies are hurt trying to jump from places they shouldn't. If she is going to be allowed on the furniture, please get some pet steps or a pet ramp (they make taller ones to put next to the bed, also). Walmart, Walgreens or Petsmart carry some inexpensive stairs that work well next to a sofa, or you can google them and find zillions of them online.
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He is your friend, your partner, your defender, your dog. You are his life, his love, his leader. He will be yours, faithful and true, to the last beat of his heart. You owe it to him to be worthy of such devotion. -- Author Unknown