Watch Kelly Ormerod's full statement following the coroner's conclusion of her parent's deaths
Kelly Ormerod was on holiday in Egypt with her two children and her parents, John and Susan Cooper, when the couple died in 2018.
A coroner concluded on 10 November that their cause of death was carbon monoxide poisoning caused by bed bug spray used in the next room.
In an emotional statement, Ms Ormerod said: "After more than five years of waiting, we have finally been given closure today on the cause of mum and dad's death.
"No matter what the outcome today brought, nothing would make up for the pain and loss we felt since that day."
John and Susan Cooper had been well until suddenly falling ill in the early hours of 21 August 2018.
A two-day inquest into their deaths heard the hotel room next to theirs had been fumigated with chemicals to kill bed bugs just hours before.
Mrs Ormerod said a strange smell had been present in the room "like acetone, like someone had painted their nails".
Following the coroner's conclusion, Ms Ormerod said: "To this day, our family struggle to comprehend what happened.
"It should have never been allowed to happen.
"The last few years have been the most traumatic and emotional time for all of us involved.
"While time has moved on, its stood still for our family because of the many unanswered questions we have had", she added.
The family's solicitor, Jatinder Paul, said the circumstances surrounding the couple's deaths were "shocking" and "deeply concerning".
He said: "Losing John and Susan in such sudden and tragic circumstances, continues to have a profound impact on the family, including Kelly.
"What's made their grief all the harder has been having so many unanswered questions regarding their death."
Mrs Ormerod said their family "is broken" after her parent's tragic deaths.
She said: "There's now a huge void in our lives and I don't think we will ever fully come to terms with losing them the way we did, they were both fit and healthy.
"Having to relive everything at the inquest has been harrowing but it was something we had to do for mum and dad.
"Whilst I must look at this as a positive outcome that we do finally have that answer, it's extremely difficult to digest.
"Our family has been broken."
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