A father accused of driving his car into a freezing Worcestershire river in an attempt to murder his two children has told a jury: "They were my world."

Christopher Grady's five-year-old daughter Gabrielle died after being trapped underwater. His then six-year-old son Ryan, who was on the back seat of the car when it began to sink, was rescued by police divers.

Grady, 42, who allegedly rang their mother warning her she had seconds to say goodbye to her children, denies murder and attempted murder.

On Friday, at the start of the defence in his trial at Birmingham Crown Court, Grady was asked by his lawyer Timothy Raggatt QC how he felt about Ryan and Gabrielle.

Grady said: "They were my world, I loved them ...I had five children and I loved all of my children more than anything in the world. I still do."

Grady told the court he had been taking anti-depressant medication prescribed by a doctor "probably for about the last two-and-a-half or three years."

Grady, who also has three children from a previous relationship, said that towards the end of 2009 his ex-partner Kim Smith, 37, the mother of Gabrielle and Ryan, was "trying to stop me seeing the kids completely".

He said: "It just ground me down, it got worse and worse. The more she pushed, the more it just made me feel useless and worthless.

"I just didn't really want to live. But I did. I felt like I didn't want to live. I felt like there was nothing left but I always knew the children needed me, all five of them."

The court has heard that Gabrielle spent two hours submerged in the River Avon in Evesham, Worcestershire, stuck in her father's car after he drove into the water on February 11 last year. She died three days later.

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