Suzanne Rees was found dead on Lizard Island after being left behind by a Coral Expeditions cruise ship. Picture: Supplied.

The daughter of a woman whose dream cruise trip ended in tragedy has shared her heartache about being left without answers.

In October last year, NSW grandmother and retired accountant Suzanne Rees, 81, set off for a luxury voyage around the top end of Australia from Cairns to Perth.

The Coral Adventurer cruise’s first stop was Lizard Island in the Great Barrier Reef where Ms Rees joined a guided hiking tour on October 25.

But the experienced hiker was left behind and was found dead the following morning.

Ms Rees’ daughter Kate Rees and son-in-law Andrew Cowie have now raised questions about how the tragedy could have been able to happen in a program aired on 60 Minutes on Sunday night.

Suzanne Rees was found dead on Lizard Island. Picture: Supplied.

The pair said the Coral Adventurer had not told them why she was left behind or when staff first realised.

In the program, Kate Rees shared the final message her mother had sent her on the $30,000 cruise.

“She sent me a text that morning, um, with a photo of the deck, saying, um, ‘Arrived at Lizard Island, going for a hike, and then afternoon swim’,” she said.

“We had no reason to think that this wouldn’t be the most amazing experience. We had no reason to think anything bad would happen.”

Ms Rees said she had received little detail about how her mother came to be alone on Lizard Island but understood she’d been sent back to the ship by one of the hiking party’s guides.

“It was a person on the hike, mentioned that my mum was feeling unwell. Or ‘not too good’, I think were the words,” she said.

“And apparently, she was told to go back down to the boat.”

60 Minutes reported the hiking party returned aboard the Coral Adventurer and the ship set off for the next destination at 3.35pm.

According to the program, it was five hours before the cruise ship turned around after realising Ms Rees wasn’t aboard.

Coral Expeditions vessel Coral Adventures. Picture 7News

A search party was sent ahead at 10.30pm and a rescue helicopter dispatched from Cairns but the search was called off when the Coral Adventurer arrived at 3.30am, 60 Minutes reported.

Ms Rees was found dead 50m from the path the following day.

Speaking on the program, Fern Trent, who once guided hikes on the Coral Adventurer, said it was established practice to radio in to the ship if someone had a problem.

Ms Trent said she believed it was “shocking” to leave an unwell guest to make their own way back.

“It’s shocking that you wouldn’t radio it in. And I think what’s most shocking is that you’d missed the headcount,” she said.

In a statement provided to the program, Coral Expeditions said Ms Rees’ death was devastating.

“We are deeply sorry to Ms Rees’ family for their loss and the distress and hurt her death has caused.

“While Coral Expeditions had comprehensive safety systems and procedures in place, we acknowledge some of these were not adequately implemented on this tragic day.

“Ms Rees’ death has shocked our people to the core and we will continue to co-operate fully with the ongoing investigations.

“Coral Expeditions has introduced additional systems and procedures to further strengthen protections for our guests.”

Ms Rees said she believed the walk should have been cancelled if the conditions were unacceptable.

“Somebody needed to make that decision and say, ‘too hot, we’re not doing a walk’.”