What should I do in this awkward situation?

My dad is coming into town this month. I haven't seen him in 6 years. I have always left communication open between us, and we used to talk now and then. He and my mother divorced 20 yrs ago, as time progressed we moved further and further apart until eventually he wrote me off. I am married 12yrs with 4 children. Three whom hes met. My brother told me that he wants to see us. I'm not sure if I am ready to risk being hurt again. I have been trying to heal from this broken relationship for a long time.