What do I do about criminal tresping charges being filed against me by someone who is not the owner?

My dad is living by himself since my mother ped away a few years ago, and he has been living in his home for over 30 years. He has a "shared driveway" the whole time with his neighbor. His neighbor that he had been living next to for 30 years ped away, and his granddaughter moved in after 2 years of leaving the residence vacant and unattended. My dad and I mowed and took care of the front yard, because the gr was tall and weeds were growing about 5 foot tall, and had to do this for two years. All of the sudden, the granddaughter moves in and started calling the cops on my father. Her husband and I got into a verbal confrontation and then she called the cops. We all told the truth that no one actually crossed over each other's property line and the cop is witness to this; however, she went down and put out a warrant against me for criminal tresping. I don't understand how she can have me arrested when I have done nothing wrong. She now has my disabled father affraid to park in his driveway, and keeps threatening him about her uncle being a district attorney and helping her out. I am now having to get an attorney, and my father is elderly and disabled, and is very worried. Please help!!!!!!!What do I do?????