Cerys' parents, Terry and Julie Potter, were in court in Turkey today to hear a panel of judges hand down guilty verdicts to four men.
Her father told our reporter Kevin Ashford "We couldn't sit back and know that there were still children going on these death traps - and more children were going to get killed."
Two owners and two employees of Marmaris Rafting, the company which ran the excursion Cerys was on when the incident happened in 2010, were found guilty of reckless killing.
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The student, who has lived in the UK since she was 12, faced leaving the UK three months before completing her degree.