A first post-mortem concluded Jean Hanlon had drowned, but a second one suggested she had suffered injuries consistent with a struggle, including a broken neck and punctured lung.
Now, a decade on, authorities in Greece have reopened the inquiry into the 53-year-old’s death following a recent Channel 5 documentary about the case.
Her son, Michael Porter, said he hoped the move would lead to the family “finally getting answers and justice.”
At the time she died, Ms Hanlon, a mother-of-three, had been living and working in Crete for several years.
She went missing on 9 March 2009 and four days later, her body was pulled from Heraklion harbour.
Mr Porter said a new witness had come forward since the recent screening of the documentary, entitled ‘Murdered in Paradise: The Killing of Jean Hanlon’.
He and his family have travelled to Crete to mark to the 10th anniversary of Ms Hanlon’s death, where they released 10 balloons in her memory.
But with “unanswered questions” surrounding how his mother died, Mr Porter said he hoped the a renewed appeal would help with their search for answers.
“The circumstances and truth about what happened to my mother have never been established,” he said.
Mr Porter said they believed that on the night of her death, his mother was with a man who has still not been traced.
He added: “We have never had any hard feelings or issues with Greece or its people in relation to this tragedy and we just hope that with the right information and support we can all work together and hopefully reach a clear-cut conclusion and ultimately put an end to this heartbreaking situation and bring about the justice that she deserves.”
Ms Hanlon's granddaughter, Rebecca Porter, said visiting the island had been emotional.
She said: "It has been up and down. One minute I am absolutely fine, finding comfort in gran being here - the next thing absolutely upset and the grieving just hits you.
"It comes in waves but as soon as I landed just finding comfort - I see why gran loved this island so much."
A petition set up by Mr Porter calling on the UK government to exert pressure on Greek authorities to fully reinvestigate and review the case has amassed more than 5,000 signatures to date.