In 1993, Sirius Black escaped from Azkaban after seeing a picture of Pettigrew's rat form in a Daily Prophet article about the Weasley family's trip to Egypt.
Upon seeing the Potter's cottage in ruin, Pettigrew deduced what happened and retrieved Voldemort's wand to prevent the Ministry from inspecting it to discover his treason. Sirius deduced Peter's backstabbing from a lack of struggle at his hiding place.
Peter was taken in by the Weasleys and for twelve years lived with them as Scabbers. One day, while in Azkaban, Sirius asked Cornelius Fudge for his newspaper and saw a photo of Scabbers (aka Peter). Realising he was at Hogwarts, Sirius escaped to come and find him.
An exasperated Lupin gives each one of them back their wands, and explains that he was examining the Marauder's Map, watching Ron, Harry and Hermione exit Hagrid's cabin, when he saw the name Peter Pettigrew alongside Ron's. At that point, he realized that Peter must alive and disguised as Scabbers.
He Chose The Weasleys As Owners To Avoid The Death Eaters
Due to the fact that Voldemort's apparent demise happened due to Pettigrew's information, the Death Eaters believed that Pettigrew was a traitor and therefore sought to destroy him.
Harry Potter and the Prisoner of Azkaban - the truth about Peter Pettigrew reveald part 2 (HD)
Why did Fred and George never see Peter Pettigrew?
There are hundreds of students in Hogwarts, plus ghosts, teachers, House Elves, and Peeves. Unless Fred and George were watching Ron sleep on the map (which would be creepy), they wouldn't have noticed Pettigrew. It's only possible to see a human changed in his animagus form if you know the person is one.
Though he valued his own life more than the lives of his friends, Pettigrew felt guilt for betraying Lily and James, but didn't have the courage to admit his treachery or to turn against Voldemort.
In 1993, Sirius Black escaped from Azkaban after seeing a picture of Pettigrew's rat form in a Daily Prophet article about the Weasley family's trip to Egypt.
Werewolves might be dangerous to humans, but they don't attack other animals; so Lupin's friends found a way to stay together as a kind of pack. James's Animagus form was that of a stag, which earned him his nickname, Prongs.
As James and Lily's Secret-Keeper, Pettigrew was entrusted with the information of the Potters' hiding location in Godric's Hollow. He had not even been Secret-Keeper for a week when he handed the information over to Voldemort.
Sirius Black is introduced in the third Harry Potter installment as the Prisoner of Azkaban, a dark and menacing figure feared by the Wizarding World almost as much as Voldemort himself. Everyone believes he's a mass murderer who betrayed Harry Potter's parents to the Dark Side.
But the whole thing was a misunderstanding. No, Sirius Black was not involved in any horcrux business. It seems no one but Snape and Dumbledore were aware of this fact.
Until the climax of Prisoner of Azkaban, Lupin believed Sirius Black was guilty of murdering 12 Muggles, betraying Lily and James Potter, and killing Peter Pettigrew. He eventually discovered the truth — that Sirius was innocent, and the very much alive Peter was the traitor.
Either through eavesdropping or being deliberately told, Draco knows that Sirius could turn into a black dog and uses the information to torment Harry.
Dumbledore's lack of belief that Sirius is innocent is also suspect. Sirius was a member of the Order of the Phoenix which fought against Death Eaters, but Sirius also was as close to James as a brother, the Potters even took him in when he ran away from home.
Sirius Black was believed to be the Potters' Secret Keeper, but he secretly switched with Peter Pettigrew, who turned out to be a mole. James' bullying behavior at Hogwarts and his relationship with Peter contributed to the tragic events that led to the Potters' deaths and the rise of Harry Potter's story.
J. K. Rowling has stated that she would fancy an otter — her favourite animal — as her Animagus form, though if she actually transformed, she suspects she might be "a guinea pig or something, which would be quite embarrassing."
And there is no question that Snape was a talented wizard, and that he could have become one if he had wanted to. But the fact is, there is not one single shred of evidence in Canon that Snape ever became an animagus.
But Snape is too intelligent not to notice this. Originally Answered: Why did Snape not tell Dumbledore that it was actually Peter Pettigrew who betrayed Lily and James instead of Sirius Black? Because he didn't know.
Scabbers is Ron's rat, but later in the book it is revealed that he is really the wizard Peter Pettigrew who has taken a rat form. The Weasley family adopted Scabbers (the rat) thirteen years ago; he used to belong to Percy but was passed down to Ron when Percy got an owl.
The Order battles the Death Eaters in the "Death Chamber". During a frenzied duel with Bellatrix, Sirius taunts her for failing to harm him. Bellatrix strikes Sirius with a curse, sending him backwards into the veil and to his death.
Peter Pettigrew was a member of the Marauders before he betrayed his friends in Harry Potter, but that choice makes no sense. Even more so than the magical elements, the Harry Potter franchise can be defined by its relationships.
Scabbers was Ron Weasley's pet rat. Passed down throughout the family, by the time he came to Ron, Scabbers was living up to his name with patchy fur and a distinct preference for sleeping.
Pettigrew hesitated for a few seconds, something his enchanted silver hand interpreted as weakness. This brief moment of mercy caused his silver hand to turn against him, ultimately strangling him to death.
