However, Draco was ordered by Voldemort to kill Dumbledore. Lestrange saw this as an opportunity to test Snape's loyalty and while making this vow to always watch over Draco, Lestrange forced Snape to agree to killing Dumbledore himself in case the youngster was unable to do so.
At the same time, Snape, his true loyalty to Dumbledore, informed the headmaster of this plot, and both knew that it was no more than an excuse to see Draco fail and kill him in punishment for Lucius's failure.
Because Draco Malfoy knew what is at stake for him and his family even if he was successful in killing Dumbledore. He felt victorious after getting the position as a Death Eater, but later on learnt the horror of being one as he understood Voldemort's nature better.
Instead of suffering a painful death, he urged Snape to end his misery. He was confident that Snape was loyal to him, and his allegiance with Voldemort was simply to protect Harry, because he failed to protect his mother Lily. Ultimately, Dumbledore's death at Snape's hands was a win for everyone involved.
Draco had several reasons for lying to Bellatrix, including the fact that he was never a bad person. Moreover, he no longer found working for the Dark Lord appealing and hated how Voldemort treated his family. He did not intend to harm anyone and believed Harry was the only person capable of defeating Voldemort.
Lucius Malfoy had a strong dislike of Albus Dumbledore. This is due to two reasons – Dumbledore believed in Muggle rights which contradicted Malfoy's pure blood beliefs. In addition, Lucius was a Death Eater, so he believed that Lord Voldemort was a much more powerful wizard than Dumbledore.
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.
Specifically, Draco was jealous of Harry. It was easy to miss because Draco didn't often show his emotions, modelling himself on his cold, confident, calculating father, but J.K. Rowling has confirmed that a lot of his enmity towards Harry stemmed from envy.
“You disgust me,” said Dumbledore, and Harry had never heard so much contempt in his voice. Snape seemed to shrink a little, “You do not care, then, about the deaths of her husband and child? They can die, as long as you have what you want?” Snape said nothing, but merely looked up at Dumbledore.
At one point, Snape is named as a Death Eater by Igor Karkaroff, but Dumbledore comes to Snape's defence, claiming that although Snape had indeed been a Death Eater, he changed sides before Voldemort's downfall and turned spy against him.
After it was revealed that Dumbledore was devastated by the accidental death of his sister during a fight with Grindelwald and his brother, Aberforth, it became clear that Dumbledore's deepest desire, and regret, involved his family.
This nuance was lost on Lord Voldemort, who wrongly assumed Severus Snape held the Elder Wand because he was Dumbledore's killer, when in reality Draco had disarmed Dumbledore before Snape arrived on the scene, making Malfoy the wand's true new owner.
Using a spell from the half-blood prince's book, he nearly kills Draco's. Third Plot Point: Harry finally gets Professor Slughorn to share the memory of Voldemort's descent into dark magic.
In order to conjure the avada kedavra curse, you have to want to kill your victim. We all know that Voldemort could easily kill a child without an ounce of remorse... but not Snape. Snape didn't want to kill Dumbledore, and this was why the spell was blue instead of the usual green.
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.
Telling him the truth doesn't risk her life and neither does it risks Draco's life, who would still be a minor servant and while at the bottom of the Deatheather's hierachy, still be a part of it. Not knowing whether Draco was alive or dead, Narcissa chose to lie to the Dark Lord rather than risk losing her son.
Ultimately, his need to survive and protect his family would lead Lucius to betray Voldemort. With the Dark Lord defeated, he and his wife Narcissa turned in every Death Eater they could to avoid being imprisoned in Azkaban.
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. Lucius did that for his own benefit - he was trying to discredit Arthur weasley.
It is also probable that, since Narcissa's lie to Voldemort saved Harry's life, the family is pardoned for their crimes. They keep a relatively low profile after that, while continuing to live a leisurely life in the Malfoy Manor.
Finally, Lucius, Narcissa, and Draco never fled Hogwarts with the other antagonists and losers. In The Deathly Hallows novel, the Malfoys defect from Voldemort's army, betraying the other Death Eaters.
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.
Cruciatus Curse ('Crucio')
Harry tried to use this spell himself. The first time was against Bellatrix after she had killed Sirius.
Harry Potter and the Deathly Hallows
In this book, Rowling reveals that Bellatrix is the guardian of Helga Hufflepuff's cup (though she is unaware that it is a Horcrux), which Voldemort has entrusted the Lestranges to keep in their Gringotts vault.