This issue continues to vex, intrigue and perplex his biographers. Elvis and Jesse would have been the sibling kings of rock and roll, making Phil and Don Everly look about as charismatic as the Olsen twins.
It's hard, though, to specify what impact - if any - the dead twin had on Elvis. Elaine Dundy is the biographer who seems, to me, to have the most intuitive insight into Elvis. Her recreations of his moods and feelings are far more convincing than the robotic interior monologues that mar Peter Guralnick's magisterial biography. And she argues he felt guilty, bereaved and triumphant, especially when he realised, with relish, that his first name was an anagram of 'lives'. She even cites a handwriting expert who sees, in the boy Elvis' refusal - until he was in teens - to sign his middle name with a capital A, evidence of his continued sense of loss.
Alan Bleasdale, whose musical drama 'Are You Lonesome Tonight?' is one of the most profound explorations of Elvis' psyche, suggested that Jesse's death left his surviving brother psychologically incomplete, explaining the extraordinary passivity and odd lack of self-confidence which Sam Phillips noted and, Bleasdale suggests, Parker exploited.
Vernon Chadwick, author of the book 'In Search Of Elvis', agrees with Bleasdale that the lost twin is key to understanding Elvis. He told Time magazine: "We do know that twins who lose their partner, often suffer many problems and disorders in later life. The subject of Elvis' twin can help us understand both the great power that Elvis had to connect with an audience as if he were reaching out to connect with his absent brother, as well as the emptiness of the so-called 'black hole' which single twins often experience. Relatives and friends of Elvis in Tupelo have stated that Elvis felt guilty about the death of his twin brother, Jesse Garon. It's very likely t this guilt played a role in Elvis' later dysfunctional behavior."
Psychologists I have spoken to agree with Chadwick that the loss of a twin could have been of profound significance but caution that Elvis is too great an enigma to be decoded by reference to a single event or issue.
The people he knew best are similarly divided. For every friend like Larry Geller or family member like Billy Smith who insists that he thought often of Jesse, there is a member of the Memphis Mafia who, with equal sincerity (and no obvious axe to grind) is utterly baffled by the idea that he even contemplated his twin, let alone talked to him or visited his grave.
Elvis perpetuated the mystery because, like JFK, he was a master at editing his personality to suit his audience. This process was accentuated by the peculiar arc of his career in which he was serially marketed as many different Elvises: the rebel, the romantic, the regular GI, the king of Las Vegas, the smiling boy next door, the troubled teen who wanted to be James Dean. At its most extreme, this gave us the diametrically opposed twin Elvises: the swaggering sexy womanising rock and roller and the soulful gospel singer who sang God's music with such purity and passion it's hard to listen to songs like He Touched Me and not be swayed by the sheer power of his obvious - and deep - faith.
The loss of Jesse Garon may go part of the way to explaining the mystery of Elvis. One aspect of his extraordinary appeal - which Chadwick touches on in his diagnosis - was his secret vulnerability. That may be why so many millions felt, when he died, as if they had lost a member of the family. There was an aura about Elvis that struck even such a seasoned observer of the human species as the film director Sidney Lumet. He directed Marlon Brando in Orpheus Descending, a Tennessee Williams play that seems, as Dundy pointed out, to owe its central character to Elvis. But after watching Elvis on a set he was disturbed by what he saw as a "restless unhuman - not inhuman - spirit" that would "never be at rest anywhere".
In his later years, it's clear Elvis wasn't at rest. He kept searching for answers from books and mentors but, as Lumet predicted, never found true peace. Only a brave - or a stupid - pundit would dare to say how much of that was due to the loss of Jesse, the premature death of his mother or the collapse of his marriage. That is a lot of trauma for any man to cope with, let alone someone who also happens to be the most famous man in the world.
But as we learn more about the human mind, it becomes clearer that childhood can have a devastating impact on our lives and personalities, affecting us in ways that we - and our loved ones - don't even recognise. And that first bitter loss must have given Elvis both a powerful sense of destiny - his survival must, he probably felt, have been for a purpose - and, as his life failed to turn out as expected, a deep and disturbing sense of the fragility of it all.
- More articles by Paul Simpson