The sworn son of 1970s sex kitten Siu Yam-yam slashed a fellow student's face during a late-night chat at the star's home, a court heard yesterday. John Cheung Wan, 22, is the godson of Ngai Siu-ngan, better known as Siu Yam-yam, once a sultry starlet of the Hong Kong film world. On March 22, Ms Ngai took a group of film industry friends to dinner at a Tsim Sha Tsui restaurant. The party continued at Ms Ngai's Cox's Road flat in Jordan, where Cheung was staying, the District Court heard. She introduced Cheung to Hui Ka-kit, 24, and the pair struck up a conversation at the dining room table. Both men were overseas students and talked about life in Britain. Prosecutor Paul Dinan said Cheung left the table an hour later and returned with a knife, slashed Mr Hui and stood over his victim yelling: 'I am John! John Cheung. Don't come near me.' The victim's father, Hui Chi-keung, said: 'Cheung believed his son had been insulting. We were all sitting around chatting when this happened.' Cheung denies wounding with intent. The case continues today before Deputy Judge Louis Tong Po-son.