A man who battered his 11-year-old great-niece to death, leaving her with almost 100 “catastrophic” injuries, has been found guilty of manslaughter.

Delroy Forrester admitted killing Jasmine Forrester in an attack on February 9 before insisting “the devil had to die”.

He denied murder on the grounds he was “legally insane”, with a jury at Wolverhampton Crown Court hearing how a few days before the incident Forrester had been suffering from a psychotic mental disorder which his daughter had tried to report to a hospital crisis team.

The 51-year-old’s daughter, Tyler, was angry her father was not in hospital and had called the crisis team at Penn Hospital in Wolverhampton hours before the incident to ask for help. The hospital is a major provider of mental health services.

After saying they could not help, she said: “You’d better make sure he doesn’t kill my nan tonight.”

Forrester, formerly of Lower Villiers Street in Blakenhall, was convicted of manslaughter on the grounds of diminished responsibility after a four-day trial and will be sentenced on September 24, the Crown Prosecution Service (CPS) said.

The defendant had wanted to kill his son Myles, and was later heard speaking of Jasmine as being “pure and innocent”.

Police were called to the house of the defendant’s mother and Jasmine’s great-grandmother, Victoria Forrester, in Kent Road, Wolverhampton, in the early hours after the 79-year-old raised the alarm with her neighbour.

Jasmine was being looked after by her great-grandmother on the evening of February 8. Forrester was also staying at the address.

Jasmine’s father Simeon Forrester said in a statement read to the court: “Jasmine was vibrant, funny and loved life. That life was tragically cut short by the actions of a family member with whom she should have been safe in a trusting environment.

“I would give anything to change places with Jasmine; to take away the terror and pain she suffered that night. For the rest of my life I will feel guilt, because I was not there to protect her when she needed me most.”

Jasmine’s father he “felt numb” when he was told at the children’s hospital that her life support would be withdrawn.

“I lay next to Jasmine on her hospital bed. I cuddled her and urged her to be brave on her onward journey. No parent should ever have to do this. Through many tears I held her and watched her last breath escape her. I feel that when she died so, too, did a part of me,” the bereaved dad added.

“Jasmine’s short life enriched the lives of so many people. She will never be forgotten. She will be loved forever. My darling little girl, my shining little star. May she now rest in peace with heaven’s angels.”

Detective Inspector Ian Wilkins, from West Midlands Police, said: “This is truly one of the most tragic cases I have dealt with in my career.

“Delroy Forrester had suffered a brain tumour several years ago and treatment had left him with epilepsy. 

“While ifs, buts and maybes are easy to say, the clock cannot be turned back and the events that unfolded that night have left a family torn apart by the loss of two loved ones – Jasmine and her great-uncle.

“My heartfelt sympathies are with them as they deal with their loss.”

Giovanni D’Alessandro, from the Crown Prosecution Service, said: “Jasmine was a friendly, caring and well-liked girl who had a bright future ahead of her. This was all taken away by Delroy Forrester.

“On the night of the murder, he attacked his elderly mother and, while she tried to get help, used a series of improvised weapons to launch a frenzied attack on Jasmine, inflicting serious injuries to her head and body.

“This was a tragic incident and our thoughts are with Jasmine’s family and friends.”

Additional reporting from the Press Association.