The mother of a Bradford teenager savagely stabbed to death by her boyfriend shed tears of relief as he was convicted of her murder.

A jury at Leeds Crown Court also heard how Stephen Crowther, 26, had previously been convicted for the manslaughter of his own brother after stabbing him in the leg during a fight over a girlfriend.

Nicola Garena, 16, was killed by a single stab wound to the chest last December at the flat she shared with Crowther in Leeds.

She died in Leeds General Infirmary the following day.

Yesterday, the jury took just three hours to find him guilty.

Speaking after the case, Nicola's mother, Katrina Garena, of Ramsdale Road, Little Horton, said it was time to start rebuilding her life.

"I'm happy that justice has been done," the 39-year-old said. "I was very close to Nicola, she was my only daughter."

Mrs Garena said Nicola had said she was coming home for Christmas and leaving him just days before she was murdered.

"I had never met him before but I always knew he had done it," she said.

"I haven't really grieved yet but at least now I can start. I'll just have to take one step at a time. I'm just relieved it's all over."

Giving Crowther a life sentence, Mr Justice Maurice Kay said: "Within the space of three and a half years you killed your brother and now the young girl with whom you were living.

"You must be a very dangerous young man when you have drink inside you, when you lose your temper and when there is a knife nearby.

"You must assume it will be a very long time before anyone gives serious consideration for your release."

Crowther had always denied the murder, claiming he and Nicola, a former pupil of Buttershaw Upper School, had drank vodka, strong lager and smoked two cannabis "spliffs" at the bedsit they shared in Linden Road, Beeston, before falling asleep.

He said he woke to a loud bang and found Nicola on the sofa bleeding from the stab wound.

But forensic experts found no sign of an intruder and neighbours said they heard shouting and banging coming from the flat.

Crowther had been convicted of manslaughter in 1998 after stabbing his older brother Andrew to death following a fight over a girlfriend, the court heard.

Crowther denied the murder of his brother but later changed his plea to manslaughter and was sentenced to four years in prison.

Detective Sergeant Dean Henson, who led the case, said: "The murder conviction was the right one in the circumstances of Stephen Crowther who is clearly a very dangerous man."