The children of a woman with a mental illness who stabbed to death a widow in a city shop are calling for an inquiry into their mother's medical care.
Valerie Thomas died after being stabbed by Deborah Hancock
Deborah Hancock's family have expressed their deepest sympathy to the family of Valerie Thomas, 75, who suffered the random attack in Cardiff city centre.
They said Mrs Thomas "would still be alive today" if their mother had been given the treatment she needed.
Cardiff and Vale NHS Trust said it was unable to comment.
Cardiff Crown Court heard Hancock, 45, took an eight-inch carving knife from the shelf of the Church Street store and plunged it into Mrs Thomas' back.
Judge Mr Justice Davis told Hancock, who denied murder but admitted manslaughter on the basis of diminished responsibility, that to "some extent you are a victim".
She will serve an indefinite term in a psychiatric unit for attacking the retired hairdresser who was queuing at the check-out of a Poundstretcher store.
Hancock, of Butetown in the city, has a history of mental illness.
She was heard to say to shoppers after the attack: "I should be locked up. Perhaps they will give me the six years I want."
Her defence counsel said Hancock had made "cries for help" and that it was "clear the system let her down".
The stabbing was a random attack in the city centre Poundstretcher
Hancock's family said they were "utterly devastated" that their mother had taken someone's life.
They added: "Over the past 15 years or so, we have tried on many occasions to get help from the health authorities for our mother.
"Sometimes they listened, sometimes they did not. Sadly, our mother was failed by the system. We were not equipped to deal with her, we are not doctors or psychiatrists.
"To those who turned our mother away and saw her as a nuisance, we say 'shame on you.'"
'Considering the circumstances'
In a statement, Cardiff and Vale NHS Trust said: "For legal reasons, the trust is unable to comment on any individual.
"However as a general policy, if any family is concerned in any way about the treatment received, the trust operates a comprehensive complaints policy and we would recommend an approach via that channel in the first instance".
A spokesman for the Welsh Assembly Government added: "This is a tragic case and our thoughts are with the family of Valerie Thomas at what is obviously a very difficult time for them.
"Now that the hearing has concluded we will be considering the circumstances surrounding what happened and looking at the involvement of all of the agencies involved to determine what action needs to be taken."