Reece Platt-May was found on the popular Greek holiday island in the early hours of Thursday, West Midlands Police said.
His death comes three weeks after career criminal Robert Brown was jailed for nine years for killing Mr Platt-May’s two sons, Corey, six, and Casper, two, in February.
Police said Mr Platt-May’s death is not being treated as suspicious and his family has been notified, while the matter will be passed to the coroner.
He was last seen in public at Brown’s sentencing on 27 April when he wore a Manchester United scarf to signify his sons’ devotion to football.
The family said they felt the sentence was not severe enough and called on the Government to put in place its proposals for tougher sentences for drivers who kill made law “as soon as practically possible”.
“We don’t blame the judge for the sentence imposed but what today has highlighted is that those who rip families apart seem to get off more lightly,” the family’s lawyer Rebecca Hearsey said.
“Robert Brown showed total disregard for the law when he got behind the wheel that day and because of him we’re living a life sentence knowing we’ll never see our boys grow up, while he will be out of prison in just a few years and will be free to continue his life.”
The brothers were on the way to the park when they were hit by Brown’s black Ford Focus as they crossed the road with their mother, their two other brothers and relatives in the Stoke area of Coventry at about 2pm on 22 February.
Both boys were taken to hospital but could not be saved.
Brown, 53, who had no insurance or driving licence, had been released from prison six days before the crash and had an extensive criminal record.
One witness statement read in court had likened Brown’s driving to that of “a madman” who just did not brake in time.
Brown was found to have taken cocaine some time before the collision.
Dozens of tributes for Mr Platt-May quickly came in following the news of his death on Thursday afternoon.
Julia Hunt said: “This poor family. How much more sadness must this family endure?”
Anj Kang wrote: “I’m absolutely heartbroken for the family – especially for the two boys. God, how will they cope with this? RIP Reece.”
Louise Platt-May, the boys’ mother, described Corey as “an amazing boy” who “never kept still” and loved school, but his main passion in life was football, which his grandfather said he had a clear talent for at a very early age.
Mrs Platt-May said Casper was a “cheeky little boy, always getting into trouble” but who was “so loving and caring and constantly told his family how much he loved them”.
CCTV, exclusively obtained by Sky News the day after the crash, was pivotal in the police investigation and enabled officers to establish the vehicle was travelling at least 61mph – more than double the speed limit.
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Brown, who admitted all charges, was convicted of two counts of death by dangerous driving, driving while disqualified, using a motor vehicle without insurance and using a motor vehicle without a licence.
He is serving his sentence concurrently and will also be disqualified from driving for 10 years and six months following his release.