Cassidy Stay was the only one left alive after her estranged uncle tied up and killed her brothers, sisters and parents on July 9.
And just hours after being released from hospital, where she was receiving treatment for gunshot wounds, Cassidy has taken to the stand to speak of her ordeal.
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The 15-year-old stood in front of a packed crowd and promised never to forget her four younger siblings, nor her parents Katie and Stephen Stay.
'I'm feeling a lot better and I'm on a very straightforward path to a full recovery' Cassidy told the audience.
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'I know that my mom, dad, Bryan, Emily, Becca, and Zach are in a much better place, and that I'll be able to see them again one day' she said.
'In the Prisoner of Azkaban, Dumbledore says, "Happiness can be found even in the darkest times if one only remembers to turn on the light."'
Cassidy's uncle Ronald went on a killing spree on July 9, and had planned to kill his parents and further family members before his niece's quick thinking stopped him in his tracks.
After being shot by Ronald, Cassidy had the presence of mind to play dead until he left, and she was able to notify the authorities who then arrested him.
Cassidy called the police and told them that she thought her uncle was en route to her grandparent's house.
'Without her courage and quick thinking, we might be mourning the deaths of 20 - yes, I said 20 - people today, including myself and nearly all our children and grandchildren' said Grandfather Lyon.
What a brave young girl.