The patio is 12' long.there is 2 1/2 more feet of rock to her fence, This fence and the patio have been in place for at least 18 years. The surveyor has told her the property line is 5 1/2 feet closer to our house. We have a fence in the front and back that connect to her fence. She is saying she is going to put up another fence on the property line-over our patio--some of the concrete will wind up on her side of the new fence. She says she could take down the fence and not put one up and that neither could we because it would be on her property then. We have dogs. There has been a fence there for 18 years also. What are our legal rights?Previous owners have replaced the fence but always in the same spot. She even talked about drilling into the concrete for fence posts.It is our side door--not the back door. She has lived there for about 3 years and the fence was there when she moved in.