A five-year-old boy who was “hidden from the outside world” while isolating with Covid was murdered by his mother, stepfather and a teenager before his body was dumped “like fly-tipped rubbish” in a river, a jury has heard. Logan Mwangi, described in court as a “lovely little boy”, suffered 56 injuries to his head, face and body in the attack at his home in south Wales last summer, Cardiff crown court was told. His mother, Angharad Williamson, 30, her 40-year-old partner, John Cole and a 14-year-old boy, who cannot be identified, “coolly and callously” concocted a cover-up, the court heard. Cole and the boy allegedly dumped the body in a river and Williamson rang the police claiming Logan had been kidnapped from his home in the village of Sarn, near Bridgend. The jury was told that Williamson’s relationship with Logan was clearly “fractured” while Cole had acted “unkindly” to the boy in the past. The teenager was described in court as a complex, troubled and violent boy who did not like Logan and had threatened to kill him. On the day before Logan’s body was found, a social worker visited the family home but Williamson did not let her into the flat because, she said, Logan was isolating and was feeling “a bit up and down”, the court heard. Williamson, Cole and the 14-year-old deny murdering Logan. But Caroline Rees QC, prosecuting, said each of the defendants played their part. She said: “He would not have stood a chance against any one, let alone the three acting together. Having killed Logan, each played their part in a cover-up.” At 5.46am on 31 July, Williamson made an “apparently heartfelt” 999 call to police claiming she had woken up to find Logan missing, the court heard. She appeared to be hyperventilating and claimed he had been kidnapped. But Rees said it was a “manipulative performance”. Police quickly discovered Logan in the river. He was taken to hospital but pronounced dead at 7.15am. A pathologist found he had suffered “catastrophic” injuries, as severe as if he had fallen from a great height or been involved in a high speed crash. Experts concluded he must have suffered a “brutal and sustained” attack. Rees said CCTV footage caught Cole carrying what he accepted was Logan’s body to the river at 2.43am on 31 July. He was with the 14-year-old boy, who claims he thought it was rubbish being fly-tipped into the river. While the pair were away from the house, the light in Logan’s bedroom came on. The prosecution says this must have been Williamson. Later, Cole and the boy allegedly made a second trip out to hide Logan’s dinosaur-patterned pyjama top. Rees said they disposed of Logan’s body as if they were fly-tipping rubbish. Williamson claimed she woke at 5.30am and believed her son had vanished. She said she saw Cole and the boy assaulting Logan on 29 July, hitting him in the head and abdomen. The court was told that on 21 July Logan had been found to have coronavirus and went into self-isolation. The prosecutor said it must have been difficult for Logan and those around him for him to be confined. She said: “At the time of his death he was hidden from the outside world, there was no scrutiny.” All three defendants are also accused of perverting the course of justice. Williamson and the youth deny this but Cole admits it. Williamson and Cole deny causing or allowing the death of a child. The trial continues.