My daughter left my 3 Grandchildren with me four years ago, gave me a letter that was notarized and I have her power of attorney, she wanted to take them this weekend and drive over 1,000 miles total back and forth to a birthday party. We already had plans, so I told her no, now she is threatening me to take them whether I want her too or not, she is still not stable to take proper car of the children is there something I can do to prevent this.