Joshua Millinson murder: What drove dad Daniel Sanzone to kill his own baby son?

But police believe it could have been down to the pressures of fatherhood and his jealousy of the newborn, fearing he would then play second fiddle.

The only fact known in this sorry, horrific and appalling episode of events is Sanzone is a bitter and twisted individual.

The unemployed 23 year old was in a rocky relationship with the mother of his child, Zoe Howell. They lived together with Zoe's mother, Sharon, for almost one year.

The couple were considering getting engaged but following Joshua's birth things took a turn for the worse and they seemed to be on a break. But nothing could excuse the abuse inflicted on defenceless Joshua.

Tell-tale signs of his attacks saw the baby cry when he was left alone with the young man. Joshua suffered three assaults, the most extreme leading to brain injuries, which caused the baby to die a month later.

Investigating police officer Det Insp Jim Munro's explanation of the abuse is Sanzone's jealousy of the attention swayed away from him and to his young baby.

He feared he would play second fiddle to the child but what is clear is Sanzone showed no remorse. He stood a lonely figure in the trial, showing no emotion throughout.

Even when his partner was on the stand his head was continually held in his hands. When he was convicted by the judge, Sanzone just stood still before lowering his head in his hands again and walking out. A lengthy custodial sentence will follow. Zoe Howell was found not guilty of causing or allowing Joshua's death and was cleared earlier of a charge of cruelty.

Mr Munro said: "We can read into it that the pressure of becoming a father may well have been too much for him.

"He may well have been worried around attention that Joshua was going to take from him." Sanzone did not stand as a witness during the trial and was never questioned in open court over his actions.

He also threatened 'trouble' as doctors fought to save the infant's live.

Recalling a conversation at New Cross Hospital, Police Sergeant Tony Blakeman told the jury: "He then said 'if something f***ing happens to him now there will be trouble. Someone is getting sued."

In an exchange between Zoe Howell and police officers, days after Joshua was admitted to hospital with catastrophic brain injuries at just 13 days old, she spoke of Sanzone's behaviour since the birth. She said: "Sometimes Daniel will be shouting at me when Joshua is there in my arms and even when he is calling me a bitch. He is on 24/7 about Joshua getting all the attention and us not having as many cuddles anymore. It is like he only cares about me and not Joshua.

"He will look at him sometimes as if he didn't have a care in the world. He would say he loved him but he weren't very convincing."

The trial of Sanzone heard 19-year-old Howell, who lived with him in Whitburn Close, Pendeford, told a police officer after her arrest there were 'signs' and she found some of his behaviour 'weird'.

Both Howell and her mother, Sharon, had noticed Sanzone would switch off the family's baby monitor when he was alone in a room with Joshua. Giving evidence, Howell said Joshua would scream when alone with Sanzone but insisted she did not know her baby was being hurt.

Yesterday the jury found Sanzone guilty of murder and cruelty to a child.

Sharon Howell told the jury she had confronted Sanzone about his care of Joshua just hours before the baby collapsed on October 24.

Sanzone lost his patience with Joshua and vigorously and forcibly shook his newborn son.

The boy was taken to Birmingham Children's Hospital and spent nearly a month on life support before it was switched off.