However, she added, "The one side that the tumor's on, the vocal cord nerve may be affected by the tumor. It's very difficult to tell on the CT scan. We're hoping the chemotherapy will help the situation."
Allison herself maintains a positive attitude.
"There is a smaller chance there may be some permanent damage, but I try not to think about that," she said.
Early on, there were some fears as well.
Allison admitted that she was originally scared by her diagnosis after searching online. She has since mostly stayed away from searching for information on her illness.
When the family learned about the tumor, May Allison said she and her husband got choked up.
"(Carley) turned to us in a calm voice and said she was glad it was her and not anyone else in the family, because she knew she could handle it."
Despite being told there was a 5 percent chance that chemotherapy would affect a tumor in the trachea, the tumor has become softer since treatment and has moved away from the thyroid gland, which makes it easier to remove surgically.
No matter what happens, Allison still plans to pursue her passions. She's still thinking about a possible singing career, despite the fact that she had to cancel an audition for Boston's Berklee College of Music a few days after she was diagnosed. She looks forward to getting back on the ice one day as well.
It's that unstoppable attitude that has been the most inspirational to witness, her mother said.
"From an early age, Carley always knew what she wanted and had no fear trying to get it," she said.
"For her, every day presents a new opportunity to take a step closer. The interesting thing about Carley is that she actually enjoys the journey as much as achieving her goals. When things don't go according to plan, she rallies quickly and moves on. She has the ability to make anything fun and finds it very difficult to sit still."
"She's been able to touch people," May Allison added. "Her public school raised $5,000 in a fundraiser for (Toronto's) Sick Kids Hospital where she's having her chemotherapy. There are thousands of dollars coming into Princess Margaret Hospital where she has the link on her blog. She's very proud of that."
In the meantime, Allison continues to inspire people on social media with her positive attitude.
"For me to be able to reach out to other people throughout all this has been great," she said. "People want to hear from me and hear my music right now so it keeps me happy. I cherish every moment. I have a different perspective on everything now. In the end, I think it will make me a better person."