Michael John Pearce was supposed to babysit his girlfriend's six-week-old son to give her the first night out since the boy was born, but instead Pearce ended up beating the baby repeatedly with a shoe and plastic bottle until he died.
This week the Welsh man was found guilty of manslaughter in the death of Alfie Sullock and faces life in prison. He was also on trial for murder charges, but was found not guilty.
After the verdict the boy's mother, Donna Sullock, said she was disappointed that Pearce was cleared of the murder charge.
"We are disappointed at today's verdict but satisfied he will still go to prison for what he has done," she said in a statement. "Whatever sentence he gets will never be long enough for taking Alfie's life away. We have been through a year of hell."
On the night of the murder, Pearce told girlfriend Donna Sullock that he would babysit the infant and let her go out for the night. Only minutes after texting Sullock to say that the boy was fine, police said Pearce called 999 to say that Alfie had stopped breathing.
The baby was already unconscious and blue when paramedics arrived. They noticed bruising to his face and chest, and in the hospital doctors discovered that he was bleeding from his brain. The boy died four days later.
An autopsy revealed that the baby had extensive injuries. Pearce told police he had no idea how it happened, noting the he left the boy along only for 30 seconds when he went to the bathroom, saying the baby was asleep when he got out.
Prosecutor Michael Mather Lees disagreed.
"This was not a moment of exasperation that can happen with a screaming child. This was a baby repeatedly beaten with objects," he said. "This is not a case of a baby developing sudden death syndrome. This was a child who was badly beaten."
On the witness stand, Sullock said she befriended Pearce when she was six months pregnant. She said Pearce began showing obsessive behavior toward her, though they continued their relationship.
Sullock said she fed and changed Alfie on the night he was abused, leaving him healthy and well when she went out for the night. At 8:43 p.m. she got a message from Pearce that read: "You can trust me you know." Just 28 minutes later, he was telling a police dispatcher that the boy had stopped breathing and felt cold.
Prosecutors were able to determine 10 separate injuries to the baby's face, which they matched to the shoes Michael John Pearce on that night.