I thank you all for helping me with this decision. I appreciate your help via the links you provided and read them carefully. We will have to re-think this. I understand the side effects are very rare however I couldn't live with myself if Sophie suffered because of a micro chip even with good odds. She is licensed but my fear of losing her comes from the fact that we are leaving on an island vacation for two weeks in a couple of months and Sophie will be staying with her groomer/trainer. She will keep Sophie in her house with her Chi. We've always taken Sophie with us but this time she can't go
. Thanks for all your input. I'm just being a nervous mommy but have to think about this.