Denniston Gilles "Dennis" Dolohov (formally known as Denniston Deedle) is a computer security specialist, and the father of Ralph Deedle. His parents were Maximillion and Whilhelmina Dolohov; he, however, is a Squib. His much older step-brother was Antonin Dolohov, famed mainly for killing Remus Lupin during the Battle of Hogwarts. Because of Denniston’s inability to perform magic, his parents abandoned him to a Muggle orphanage at age 12 and refused any further contact. He hides this information from Ralph, convincing him that he is a Muggle-born wizard. In hope of receiving a hundred thousand Euro reward, he sends a letter and a Chocolate Frog to the news program, Inside View, and then a package with the GPS, Game Deck and instructions to reporter Martin Prescott. Denniston claims to have communicated, via GameDeck, with someone on the Hogwarts school grounds but he does not know the identity of the person who used the profile name Austramaddux. It appears Miss Sacarhina urged him to send information about Hogwarts to the news program. She assured him that since he is, in fact, not a Muggle, the Muggle’s non-disclosure contract he’d signed is invalid and, as he has never signed the Magical Vow of Secrecy as a wizard, he was not breaking any laws. He leads Prescott’s crew and Detective Finney onto Hogwarts grounds.
This is later found out, a shocking revelation to everyone, especially his son Ralph. Regardless, he is able to redeem himself, and later help Harry Potter in his investigation in America.
Denniston is described as a small, pudgy man with thinning black hair and a twitch in his right eyebrow.