Family stand by autistic boy, 17, as he is jailed for 15 years for starting fire that killed his toddler half-brother

A 17-year-old autistic boy who killed his toddler half-brother after setting fire to his home openly wept in court as he was jailed for 15 years.

Jacob 'Matthew' Morgan cried as he pleaded guilty to starting the blaze that burned 14-month-old Joshua Hill to death in March 2015.

The teenager's family, from Rock Hill, South Carolina, have stood by their eldest son since his arrest and his mother, Julie Hill Dover, protested his innocence in court on Tuesday.

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Jacob 'Matthew' Morgan (left) cried in court on Tuesday as he pleaded guilty to starting the blaze that burned 14-month-old Joshua Hill (right) to death in March 2015

Investigators said Morgan (pictured in court on Tuesday) started the blaze on purpose and that he 'had a fascination with fire'

Prosecutors said Morgan waited outside the home (damaged mobile home pictured) as it burned, didn't call for help or save his younger brother, but his parents say neighbors held him back

'We have always believed in his innocence. Because we know our son, we know the evidence against is horrible, but I know in my heart that my son, my oldest son, is innocent,' she said.

'He loved his brother. All he ever wanted was a brother. He got to enjoy his brother for 14 months, which is not long enough for any of us, but it's the tragedy,' she added, according to The Herald.

Mrs Hill Dover and her husband Myke Hill - Morgan's stepfather and Joshua's father - had left Morgan to look after Joshua and said the 17-year-old was asleep when the fire started.

Deputy solicitor Willy Thomson said at a previous hearing that Morgan waited outside the home as it burned, didn't call for help or save his younger brother, all of which showed malice. 

Morgan has autism and his parents believe he was forced into admitting to starting the blaze

But Morgan's parents said he was told to stay away from the fire by his neighbors, who held him back as he tried to get back inside to save his sibling.

They also argue that Morgan, who also has developmental issues and struggles to read or write, admitted starting the fire under duress after a five-hour interrogation, which was not recorded. 

Investigators said Morgan gave them a number of different accounts about how the fire started. 

First he said he accidentally threw a pillow near a heater, but later he said he lit a pillow on fire and through it in the air, authorities said.

Fire experts said evidence suggested two fires were started, with one in the living room and another on a blanket in the master bedroom, where Joshua was sleeping. 

Prosecutors also argued that Morgan told police he was fascinated by fire and had set one in the house two weeks earlier. 

Mr Thompson said: 'The defendant ultimately admitted that ... he had never gone back to sleep ... that he was playing with tea candles and that he was lighting them up and had a fascination with fire.'

At a preliminary hearing last year, Morgan broke down in tears and collapsed on the floor as prosecutors spoke of the trailer park fire that killed Joshua. 

The teenager cried in court again on Tuesday as he pleaded guilty to involuntary manslaughter, unlawful conduct towards a child and third-degree arson.

Morgan's mother, Julie Dover Hill, said he would never have hurt his half-brother and that he is innocent

'We have always believed in his innocence': Mrs Dover Hill maintains that Morgan was not responsible for Joshua's death

Morgan's stepfather Myke Hill, Joshua's father, said his stepson was not a 'cold-blooded killer'

On the arson charge, he used the Alford plea - whereby he accepted punishment for the offense but does not admit responsibility for it. 

He was originally charged with murder, but this was dropped as part of a plea deal.

Addressing the court as he was sentenced, Morgan said: 'I love my brother. I still do to this very day, he's my best friend. To kill him, would be killing a piece of myself. He was the only brother I ever had and I just wish I could have gotten to him in time.'

Morgan was jailed for five years for the involuntary manslaughter charge and 10 years for the unlawful conduct charge. The sentenced will run consecutively, meaning he will face 15 years in prison.

He was also sentenced to 15 years for arson, however this was suspended to five years' probation. 

Mr Hill spoke after the hearing and said Morgan was not a 'cold-blooded killer'.

'The kid called his mom at work, crying because one of the newborn kittens was sick and he thought it was dying,' he said. 

'I'm not gonna have any sheriff, any investigator tell me to my face that he's a cold-blooded killer when he cries at Disney movies.'

Morgan's lawyer said the teenager is a 'very gentle soul' and will struggle behind bars, adding that the case was one of the hardest he had dealt with.