In the book, Bellatrix did not kill Sirius using <i>Avada Kedavra</i>: she used some kind of red spell which propelled him through the Veil. It was passing through the Veil which killed him, not the spell, hence why Harry thought he might still be alive somehow.
Recent Comments
NotACat commented on These Sounds Will Confuse Your Brain
9/8/2015
0
NotACat commented on 17 Reasons J.K. Rowling Should Seriously Consider Publishing A "Harry Potter" Prequel
1/22/2014
6