Child sex abuse images on a teenager's phone sparked a row which led to his brother being accused of killing their stepfather.

Douglas Herridge had borrowed his brother William’s phone to make a call and was disgusted on seeing the images.

They argued at their Dartford home in November 2016 and their mother Ina Herridge and stepfather Colin Payne, 54, intervened.

There was then a heated argument between Douglas, then 17, and Mr Payne, who was a champion over 50s squash player.

Three days later they clashed again and Douglas floored 6ft 4in tall Mr Payne with a single punch, causing a fatal brain injury.

Douglas, now 18, was in May last year acquitted of manslaughter.

The judge had directed the jury to find him not guilty of murder.

William Herridge, 19, appeared at Maidstone Crown Court this week accused of voyeurism and seven charges of making indecent images of children.

Because he has severe learning difficulties and found unfit to plead, the jury only had to decide whether he “did the act”.

He was found to have done the act on all charges except one of making indecent images of children.

Prosecutor Simon Shannon said 274 indecent images covering all levels of seriousness were found on electronic devices belonging to William.

Officers also discovered film of a naked girl which had been uploaded to a computer.

Officers went to the family home in Sackville Road on November 22 2016 - three days after Mr Payne died.

Judge Adele Williams told jurors the teenager could not play a meaningful role in proceedings.

Sentence was adjourned until May 4 to assess whether a mental health treatment requirement should be attached to a supervision order.

She noted Herridge had been able to undertake an engineering course, despite his learning difficulties and that filming of the girl had required “some determination”.

Merry van Woodenberg, defending, said Herridge had “different intelligences and different abilities” and trouble retaining and communicating information, but had an assigned local authority youth worker for his educational needs.

The jury was not told about Mr Payne's death or the circumstances surrounding it.