Aleisha says listening to Justin Bieber's songs helped her endure her treatment. Now she's excited she'll be going to see him in concert when he comes to Toronto.
It's all thanks to five-year-old Jacob Leon.
Jacob is a die-hard Bieber fan too.
He has the moves, the hat and the shoes. But he also has a big, big heart.
"Jacob is a different kind of five-year-old," said his mother Devon. "He is the most giving, caring, helpful child."
It all started when Jacob helped raise money for Pencils of Promise — a charity Justin Bieber supports.
It gave Jacob an idea and when his mother got tickets to Bieber's upcoming Toronto concert Jacob's response wasn't what she expected.
Jacob said he want to "give them away to somebody else ... because I want to make somebody else happy."
After searching for children's charities Jacob and his mom found Camp Trillium - a camp for children with cancer - and decided it was a perfect fit.
"I wanted it to be something that was 'Going to make kids happy,' as he said and I thought that seems like a place that was already doing that," said Devon.
Jacob decided to donate his tickets to Aleisha who was diagnosed with breast cancer and had a mastectomy at the age of three.
"She beat it. She's a survivor and a warrior," said Aleisha's mum, Melanie Hunter.
When asked how she feels about going to see Bieber, Aleisha said, shyly, "good."
For Devon Leon it's a great feeling.
"I just tell him [Jacob] everyday how amazing he is, and how proud I am of him, and I hope he realizes what an amazing thing he's doing,"