A woman accused of murdering her five-year-old son has told a jury his stepfather violently attacked her “beautiful, happy boy” two days before he was found dead in a river. Angharad Williamson, 31, claimed her 6ft 4in partner, John Cole, 40, punched 3ft 5in Logan Mwangi twice in the stomach, causing him to land hard on the floor. Williamson told the jury at Cardiff crown court that after Logan got up a 14-year-old boy, who cannot be identified for legal reasons, swept Logan off his feet and pushed the child’s head into the floor. Cole, 40, Williamson, 30, and the 14-year-old boy deny murdering Logan, whose body was found in a river close to his home in the south Wales village of Sarn on 31 July last year. He had suffered more than 50 injuries including severe internal damage to the stomach area. Williamson claimed Cole attacked Logan after the couple had an argument over damage to a stereo. She said: “It escalated very quickly. I was talking to Jay [John] in the kitchen as that’s where my stereo was and straight away he said: ‘It could have been Logan.’ “I said: ‘Why are you always blaming Logan?’ He said: ‘Stop shouting, when women shout people call the police.’ I said: ‘That’s double standards because you shout all the time, why can’t I shout?’ “Jay said Logan was smirking and he said to him: ‘You love it when me and your mum argue.’ He pulled Logan into the hallway; he tried to talk to him and Logan stuttered and wouldn’t talk to Jay. “I said: ‘Leave him alone’ but he said: ‘No I’ve had enough, he needs to talk to me’. Logan stuttered again and Jay punched him twice in the stomach and it knocked him on to his bum and he hit his elbows on the floor.” Williamson said Cole blocked her from helping Logan, who got up. She told the court that Cole said to the youth: “If he flinches again or stutters, sweep him.” Williamson said this was a martial arts move, sweeping an opponents’ legs away. Logan’s mother said the youth obeyed and swept the younger boy off his feet and pushed his head to the ground. The court heard Williamson said Logan did not seem in pain or discomfort on the day before his body was found, although he had refused to eat his favourite meal of pizza and chips on the Friday evening. She said after putting him to bed she took her medication and went to sleep at about 10pm. When she woke at about 5.30am, Logan was not in his room and she began looking around the flat and outside for him, eventually calling the police, Williamson said. Peter Rouch QC, defending Williamson, said: “The prosecution suggest what happened then was a sham by you and make-believe. Is that true?” Williamson said: “You can’t fake feelings like that. I was so scared. My worst nightmare had come true. He was gone. He was my little boy and he was out there on his own.” Rouch said: “When you got up in the morning, did you know what had happened that night? John Cole taking Logan’s dead body to the river?” Williamson said: “No, I didn’t.” Williamson previously told the jury Cole was “strict” with Logan and would leave him standing in a “naughty corner” for up to 30 minutes at a time. She said: “I thought Jay was trying to help the family, get structure in. I didn’t realise how strict he was and how scared Logan was.” Cole has admitted taking Logan’s body from the flat in the early hours and leaving it next to the river but says he does not know how the boy died. Williamson denies any involvement in her son’s death, saying she slept the whole night through and woke to find him missing. At the start of her evidence she described Logan as the “perfect baby”. She said: “I loved the bones of that boy. Logan was my little sidekick. We did everything together, he was such beautiful a happy little boy. “He was so clever, he wanted to explore the world and see what it was about and I was so proud, so proud.”