"The witch twins? Oh they are terrifying but in the end of the day they are nothing but two spoiled brats. Aro’s favorite little prince and princess. They can do whatever they want and Aro, blinded by his lust for their powers, would never punish them.
Jane is just for the show. Making Volturi seem frightening and making people fear them. But when it comes down to the real deal, Alec is the silent power. The Volturi still exist because of him. No one would ever dare to attack them because Alec can bring any enemy down, regardless of size or power, without even touching them.
Aro would sacrifice anyone from the Volturi even his wife or Caius and Marcus if that meant he would get to keep the twins. They are far more important from what they seem. Only Jane and Alec alone could take over the Volturi and the whole vampire world without needing support from anyone else. But just as Aro lusts for their powers and has grown to love them, the same applies to the twins. They lust for affection and acceptance. Aro gave them that and more. He is the father they never had, even if they had the chance to betray him, they would never do it.”