LYNN – Betty Cooper held up a worn, wrinkled picture of her oldest daughter she carries in her wallet.”She was always smiling. That’s just how she was,” she said during a recent interview.Cooper’s daughter, Cheryl Senn, died in Lynn on July 30, 1997 after her husband of 14 years and father of her four young sons stabbed her to death. The man was jealous, Cooper said, because Senn, then 29, had started taking classes at Operation Bootstrap, an adult education center with the goal of becoming a real estate agent.”I always tell my children, ‘It’s never too late to get your education.’ He was jealous of her because she was getting her life together,” Cooper said.For the past eight years, Cooper has been participating in the annual Walk for HAWC, or Healing Abuse Working for Change, which she said raises money for programs against domestic violence.Cooper, a Lynn resident for about 30 years, began participating in the walk nearly a decade ago, after hearing that Nancy Coffey, one of Senn’s former teachers at Operation Bootstrap, had already been walking in Senn’s name for several years.”I do it because I don’t want anyone to forget her,” she said.Formerly known as Help for Abused Women and their Children, HAWC provides services and support to victims of domestic violence in 23 cities and towns on the North Shore, according to a press release from the agency. Each year the walk raises more than $150,000 toward its program. The 20th annual Walk for HAWC begins Sunday at noon on Salem Common, according to the release.In 1997, Senn’s boys were ages 8, 9, 10 and 11. Today they are grown and two are college graduates. Sometimes they walk with Cooper and some years they just can’t face the memories that surface, she said.”I ask if they want to walk, and if they look at me a certain way, I know the answer is no,” she said.Cooper said she is proud of her grandsons for overcoming the tragic hardship life dealt them – a father who killed their mother.”I’m so happy they’re so well-mannered,” she said.Cooper has four other children, who walk with her yearly. The walk never gets easier, she said, and this year may be her first time walking without Coffey, who retired from Operation Bootstrap last year.”It’s no different. It’s harder. It feels like he stabbed me, right here,” she said, clutching her side. “It’s hard.”Cooper said it will be hard for her to miss her church’s anniversary after all it has done for her. On Sunday she passed around a pamphlet, and members of her church, Cathedral of Faith, each put down a pledge in Senn’s memory.”Without faith I couldn’t go on without my daughter,” she said. “It’s just I don’t want it to happen to anyone else like it happened to me.”Taylor Provost can be reached at [email protected].