Maria Stubbings, of Chelmsford in Essex, was strangled with a dog lead in 2008 by Marc Chivers, who had already killed a previous girlfriend.
Her brother Manuel Fernandez has told ITV Daybreak that the family have been calling for a public inquiry.
He said: "This highlights issues around domestic violence with one police force but it's actually a national problem."
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British Bankers' Association head Anthony Browne warned that some banks could be moving abroad within weeks due to Brexit uncertainty.
Labour said its plan would mean grieving families would not have to pay for either a burial plot or cremation for a child aged under 16.
The children are among around 70 new young arrivals to arrive in Britain under the landmark Dubs amendment.