The missing key. Plus the stunning admission. I still love my dad today. Nightline will be right back. Nightline continues. Here now, deborah r on february 25th, 2005, when i found out my father was arrested, this place became not my home. And no one ever slept in my house again. He calls himself the btk strangler and promises to kill again. The brutal crime shocked wichita. The most unsolved killing spree in wichita history. Btk stood for bind, torture, kill. That was his mchb. O. Reporter three letters which can touch off memories for anyone who lived in wichita in the 1970s. He would see a woman walking, and he would say shes next. One minute had a loving father. Right. Reporter the next minute, hes a serial killer. I mean, come on, the child of a serial killer actually talking about it . Thats something you almost never hear. Kerry rawson was 26 years old on the day she learned her father was the cold blood killer known as btk, responsible for killing ten people and terrorizing wic