At the end of GOF only a handful of people even know that Sirius is an animagus, let alone his loveable big doggie form. But by the beginning of OOTP we have Lucius Malfoy able to "recognize" Sirius by seeing the large black dog with Harry.
Harry had been working on his Patronus charm, though, and Malfoy & Co. got what was coming to them. One of the most notable Malfoy moments is where he hints that he knows all about Sirius Black (7.1. 48).
He didn't mention that Sirius was an Animagus to Dumbledore because he didn't want to admit to breaking his trust while at school. All in all, Remus did the most to help Harry and the wizarding world.
Lucius Malfoy most likely knew Sirius Black was innocent. Lucius Malfoy was one of Voldemort's closest followers in the first war, one of only three Death Eaters entrusted with the protection of one of Voldemort's Horcruxes.
“Technically, it's a ferret.” Barty Crouch Jr. may have been completely wrong to transfigure Draco as a punishment, but he was within the same family of what I believe Draco's Animagus form would take, which is the stoat, or ermine.
“A creature I wouldn't want to kiss . . . a spider!” Harry figures out the riddle, and realizes that a spider is about to attack. But what he doesn't realize is what I now believe: that the spider in the maze is Professor Snape, in his Animagus form. It is Spider/Snape who bears down on Cedric and Harry.
J.K. Rowling says Draco doesn't have a patronus because he never learned the spell but I think it's because he doesn't have any powerful happy memories to use.
The answer is that Sirius wanted to deflect attention from the real Secret-Keeper. He probably hoped Voldemort would go after him so he could steer attention away from Pettigrew.
Lucius Malfoy may be one of the Dark Lord Voldemort's Death Eaters, but that doesn't have to mean he's a bad father or that he was cruel and had hurt/abused his wife, Narcissa Black Malfoy, and son, Draco Malfoy.
Lily's blood and protection lived on and would last until he came of age. Therefore, if Harry had gone to live with Sirius while he was still underage, he would not be safe from Voldemort.
Harry discovers this in Prisoner of Azkaban, when his Patronus turned out to be a stag, his father's Animagus form.
Sirius's early life proved unhappy; he had come to hate most of his relatives, in particular his mother. He rejected his family's pure-blood elitism and reverence for the Dark Arts. At Hogwarts, rather than be sorted into Slytherin like the rest of his family, Sirius was placed in Gryffindor.
They are James Potter, Sirius, Wormtail, Skeeter, McGonagall, Talbott Winger, and an unnamed witch who can turn into a cat. The fact that there are so few Animagi just causes us fans to want to know more about them. After all, they are some of the most unique characters in all of Harry Potter.
Draco Malfoy's mother Narcissa was cold, cunning and devoted to the Dark Lord. But she was also a mother, which meant she was willing to risk everything to make sure her son was safe. When Harry survived Voldemort's Killing Curse for the second time, Narcissa pretended he was dead so she could get to Draco.
She asked him because if Draco was still alive, she had something to fight for. She had a reason to lie to Voldemort. If Draco is alive, she needs to get into the school to see him and protect him, and helping Harry feign death was the easiest way to do that. But if Draco was already dead, she wouldn't have bothered.
Narcissa's greatest moment, however, was when she chose to betray Voldemort in Harry Potter and the Deathly Hallows. Not knowing whether Draco was alive or dead, Narcissa chose to lie to the Dark Lord rather than risk losing her son.
In fact, Lucius' own support to Voldemort is revealed to come only under some form of duress, which is likely Narcissa's Veela Allure. When Lucius turns on Voldemort due to the reveal of his Horcruxes, Narcissa divorces him, taking 75% of Malfoy's wealth with her.
Why? The main reason is that Lucius failed to retrieve the prophecy from the Ministry of Magic, put that on top of all the other times Lucius failed, and it leads to him losing any clout he once carried within the Death Eaters.
Isaacs brings up Lucius' disheveled appearance in Deathly Hallows, raising the possibility that the Malfoy patriarch had begun drinking too much. The way Isaacs saw it, Lucius was in a no-win situation. Given everything he'd done, the man no longer had a place on either side of the war.
Bellatrix Lestrange Killed her own cousin, Sirius Black: She killed Sirius (who was her cousin) during the battle at the Department of Mysteries. She was remorseless and was cackling in glee after she had murdered Sirius.
Amelia Black, the daughter of alleged mass murderer Sirius Black and Sierra Snape, Severus Snape's sister, struggles most of her life to get her father's attention.
Dumbledore didn't know for certain that Sirius was innocent, and for the most part, it didn't matter. Sirius wasn't useful. Also, see Remus - Dumbledore saw no use for him, so didn't help him.
Therefore, figuring out a spell that is Draco's favorite is hard and, in the movies, there is no defining moment that cements a spell as his favorite. Based on Harry Potter lore, and an article by The Healthy Journal, Draco's signature spell is a N.E.W.T standard spell, The Protean Charm.
1 Albatross
As the rarest Patronus in the Wizarding World possible, the Albatross represents an enormous bird that flies freely across any sea. This rare Patronus represents those who are simultaneously fearless, optimistic, happy-go-lucky, and ambitious.
If Draco had been a Gryffindor, he still would have had parents strongly affiliated with Lord Voldemort and Bellatrix Lestrange as an aunt. Malfoy Manor would've still been a good base for Voldemort. Dumbledore would remain a major threat and Malfoy would have been in a good position to get close to him at school.