Dudley Dursley is the only son of Vernon and Petunia Dursley, making him the Muggle cousin of Harry Potter. For most of Harry's childhood, Dudley served as a primary antagonist, being a spoiled, greedy, and brutish bully. He lives with his parents at Number Four, Privet Drive. Dudley's character undergoes significant development following a traumatic encounter with Dementors, culminating in a moment of reconciliation with Harry before his family goes into hiding during the Second Wizarding War. He represents the ignorance and prejudice of the non-magical world but also demonstrates a capacity for change.
Born on 23 June 1980, Dudley was doted on and excessively spoiled by his parents from birth. He grew up receiving lavish gifts and praise, which fostered a selfish and demanding personality. His parents saw him as a perfect child, referring to him with pet names like “Diddy” and “Popkin.” In contrast, his cousin Harry Potter, who came to live with the Dursleys as a toddler, was treated with neglect and cruelty. Dudley, along with his gang of friends including Piers Polkiss, often engaged in a game they called “Harry Hunting,” which involved chasing and beating up Harry. When Hogwarts letters began arriving for Harry, Dudley showed immense jealousy over the attention Harry received. During the family's flight from the letters, on Harry's eleventh birthday at the Hut-on-the-Rock, Rubeus Hagrid punished Dudley for eating Harry's birthday cake by magically giving him a pig's tail, which later had to be surgically removed. Dudley went on to attend his father's old private school, Smeltings Academy.
Throughout his early teenage years, Dudley's behavior remained largely unchanged. He was placed on a strict diet before Harry's second year at Hogwarts, much to his displeasure. During the summer before Harry's fourth year, Dudley and his family were tricked into eating a Ton-Tongue Toffee enchanted by Fred and George Weasley, which caused his tongue to swell to an enormous size. By the age of fourteen, Dudley had taken up boxing and became the junior heavyweight inter-school champion. His physical appearance changed from fat to muscular, though his bullying nature persisted. A significant turning point occurred in the summer of 1995 when Dudley and Harry were attacked by two Dementors in the alleyway near their home. Harry saved his cousin by casting a Patronus Charm. The Dementor's attack forced Dudley to relive his worst memories, giving him a profound insight into his own character and how he treated others. This event left him withdrawn and deeply shaken, marking the beginning of his transformation.
In the summer of 1997, as Lord Voldemort's power grew, the Dursleys were forced to leave Number Four, Privet Drive and go into hiding under the protection of the Order of the Phoenix. Before their departure, Dudley stunned his parents and Harry by expressing concern for Harry's safety, asking why he wasn't coming with them. In a moment of genuine gratitude, he shook Harry's hand and thanked him for saving his life from the Dementors. This act served as their reconciliation and was their final interaction in the series.
J.K. Rowling has revealed that in adulthood, Dudley and Harry remain on “Christmas card terms” and that their children would occasionally visit one another, though the cousins themselves never became close friends. Dudley is married and has two Muggle children. (J.K. Rowling interview).
As a young boy, Dudley is described as a large, blond child with a pink face and small, watery blue eyes. He was immensely fat due to being spoiled with food by his parents. After taking up boxing, his physique transformed from overweight to broad and muscular, though he retained his blond hair. Initially, Dudley's personality is that of a quintessential bully: cruel, selfish, greedy, and unintelligent. He throws tantrums to get what he wants and enjoys using his size and strength to intimidate others, especially Harry. He is a product of his parents' indulgence and their prejudice against anything magical or different. The Dementor attack fundamentally alters his perspective. The experience forces him to confront his own cruelty, leading to a more introspective and considerate nature. His final act of thanking Harry shows that he has developed a conscience and a capacity for gratitude, marking a significant and redemptive change in his character.
Dudley is a Muggle and possesses no magical abilities. His primary non-magical skill is boxing, in which he excelled, becoming a regional school champion.