Murdered teacher's children appeal to attacker to hand himself in Betty Yates's children, David and Hazel, appeal for help catching her killer. The son and daughter of a 77-year-old woman murdered at her "dream" riverside cottage have said they are bewildered over why she was killed and appealed for the attacker to hand himself in. Retired teacher Betty Yates was attacked with her own walking stick and stabbed in the neck at her secluded home near Bewdley in Worcestershire this month. At a police press conference her daughter, Hazel, said: "We are devastated by the dreadful manner in which our mum met her death. We are completely bewildered as to who would carry out such a savage attack on our mother. That this should have happened in her home makes this even more difficult to bear. Our mum and dad searched for many years to find this house and then built their dream and not just in bricks and mortar. Our father, Ray, died almost seven years ago and there was never a possibility in our minds that mum would want to leave the cottage. She was so happy there. It is a truly beautiful place filled with shared family memories. She added: "This has been such a hard time for us. To lose your mum is always dreadful but to lose your mum like this when you worry constantly about how frightened she might have been and what she might have felt during such a vicious attack is like a nightmare. At the moment we don't know if it was a burglary or if there was any other reason. It is possible our mum knew who killed her and this only make things worse. I go through scenario after scenario trying to work out what happened. "Please, if you know anything about this, come forward," she said. If you have done this then please hand yourself in. If you are protecting somebody please think how we are hurting and tell the police what you know. Yates spent Christmas with her family and returned home after celebrating her birthday with them on 28 December. She is believed to have been killed on 2 January. Police are working on a number of lines of inquiry. A £10,000 reward has been offered and the murder has featured on the BBC's Crimewatch. Yates's son, David, said his mother had been "full of life." He said: "She spent most days at a local hotel and was a member of a walking group. She had been a teacher before she retired and she remained in contact with many of her ex pupils. She always wanted to know how they were getting on. Since Dad's death she has busied herself because she missed him. She ran a book club and attended art sessions. She volunteered for the Bewdley festival and had recently gone to a local school to listen to pupils read. She was at the heart of the community in Bewdley and we know from the cards we have had how much she was loved and how she will be missed. It is striking how many people described her as a second mum and of course we know how much we meant to her ex-pupils. We have been asked by friends and family how we feel about who killed our mum. This is really difficult because we are at a loss to understand who could have done this and what we really need is some kind of explanation. Police are particularly keen to trace anyone who may have visited the cottage, however innocently, between 28 December and 2 January. Officers have examined two anonymous letters sent to police and a local newspaper about the killing.