A shocking twist has emerged in the case of a British grandfather accused of trying to drown his daughter-in-law during a family holiday in Florida.

The family had been staying at the Solterra Resort in Davenport, about 65 kilometres south of Orlando, when the incident occurred last Sunday.

What reportedly began as a dispute over Mark Gibbon’s will quickly escalated into violence, with the confrontation between Mr Gibbon and Jasmine Wyld ending in the resort’s swimming pool, according to local authorities.

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Now, in a startling development, it has been revealed that the two had allegedly been in a romantic relationship for the past two years.

A family source told the Daily Mail that Mr Gibbon and Ms Wyld became close after they both separated from their respective partners.

“Mark and Jasmine have been seeing each other for a few years, but they’ve never admitted it,” the source revealed.

“They do an awful lot together and they go away on holiday with the children a couple of times every year.

“They went to Florida two years ago and have been to Budapest where she posted pictures of them together like a couple.

“I don’t know for sure what happened on this holiday and why Mark has apparently tried to drown her.

“But I have been told that Jasmine was unhappy that they have been in a relationship for a few years and she is not named in his will.”

Ms Wyld separated from Mr Gibbon’s son, Alex, in 2021. Though no longer a couple, they continue to raise their two children together.

Meanwhile, Mr Gibbon divorced his wife and now resides alone in a million-dollar property in Beaconsfield, which he bought in 2023.

Past tensions between Mr Gibbon and his son had already created serious rifts within the family.

In 2024, Alex served a prison sentence after an explosive confrontation in which he reportedly drove an £80,000 ($164,000) Porsche Cayenne into his father.

The year before, the two had also publicly fallen out when Alex suddenly left the family business under unexplained circumstances.

The insider confirmed that father and son are no longer in contact.

“He feels an awful betrayal at how his dad has struck up a relationship with the mother of his two children,” the source said.

Mr Gibbon is now facing a single count of attempted murder and two counts of felony battery as a result of the drowning attempt.

While admitting to holding Ms Wyld “underwater a few times”, Mr Gibbon claims it was never his intention to drown his daughter-in-law.

Mr Gibbon is being held at the Polk County Jail without bail.