Shelleen Soltys, a single mother of four, was diagnosed with stage 3 colorectal cancer in 2012.
When she heard the news, her younger sister Christine Coleates bought a house in Camillus, New York, and invited Soltys’ entire family – four kids, two cats and two Pomeranians – to move in with her and her fianc , Joel Bennett.
“[Christine] was totally my rock,” Soltys, 41, tells PEOPLE. “She just took over and said, ‘This is what’s gonna happen – you guys are gonna come live with me, and me and Joel are gonna help you with the kids and take you to treatment.’ ”
Soltys underwent radiation followed by major surgery to remove a large tumor and then six months of post-operative chemotherapy. During that time, a simple mistake by her pharmacy sent her to the hospital.
“The pump was supposed to feed the medicine slowly over 16 hours and somehow it was set for double time,” Soltys says. “I ended up being hospitalized.”
This shocking episode led the young mother to re-examine her role in her treatment.
“In the beginning, I didn t want to know the details because they scared me,” she says. “I said, ‘Just do whatever you need to do to fix me.’ ”
But after the incident, she “realized it’s extremely important to know as much as possible because accidents do happen.”
Soltys began to focus on alternative treatments, like vitamins, herbs and a plant-based diet that could improve her quality of life while she underwent chemotherapy.
A few months later, Soltys’ doctors discovered two additional tumors. While she was preparing for a longer and riskier second surgery, tragedy struck the family yet again.
A Second Diagnosis
Coleates, 39, was on vacation with her fianc in May 2014 when she noticed an odd tingling sensation in her mouth that was accompanied by pins and needles in her legs. Upon returning to work, she blacked out and was taken to the ER where doctors discovered a 4.5-inch tumor in her brain.
The tumor was determined to be stage 4 glioblastoma multiforme, an aggressive form of brain cancer that her doctors told her was guaranteed to return.
“With chemo and radiation, a glioblastoma patient is expected to survive an average of 15 months,” Bennett tells PEOPLE.
Coleates’ strong desire to take care of others made the diagnosis especially difficult.
“One of the things that was really devastating was that she couldn t give to everybody else as much as she used to,” Bennett says.
RELATED VIDEO: How One Doctor Solved a Medical Mystery for Three Families
After undergoing a second brain surgery, Coleates lost the use of her right arm and it became difficult for her to speak and walk.
Although Coleates can no longer care for her sister the way that she used to, Soltys says, “she’s still smarter than the rest of us.”
A Special Bond
The sisters, who are the youngest of seven children, have always been inseparable.
“When we were little people, thought we were twins because we were so close,” Soltys tells PEOPLE. “We’ve always had a little telepathy going on.”
“We get a lot of strength from each other,” Soltys adds. “Everything happens for a reason, and we’re just battling together.”
Bennett recalls how the sisters helped each other through months of recovery after undergoing major surgeries just weeks apart. “They were bound to couches and talking with each other and just recovering,” he says.
“Our minds were going a mile a minute trying to figure out how to fix stuff,” Soltys says. “We’re always aware of each other’s needs, and we wanted to do more for each other than we physically could.”
Together, the two sisters do everything they can to keep healthy and remain positive.
“When we wake up, we focus on living, not on dying,” Soltys says. “Neither one of us is supposed to be here right now – and we are – and we’re very much alive, and we’re just gonna keep going,” Soltys tells PEOPLE.
“We share a special bond that a lot of other people never get to experience. And even on the bad days we still have happiness because we are still alive and we are still together,” Soltys continues.
Soltys’ children have also been a great inspiration to the sisters.
“My four kids keep me going – that’s my life and my heart and my world, but it’s also the same for Christine,” Soltys says. “She has always considered my children her children.”
A New Hope
What Coleates and Soltys want more than anything is to be able to support others struggling with cancer in the same way that they have supported each other.
“When Shelly was first diagnosed with her cancer, Christine had this idea,” Bennett tells PEOPLE. “She thought we should start some kind of foundation to help other people who are going through the same things Shelly was going through.”
After undergoing an experimental treatment in Mexico that greatly improved her quality of life, Coleates became even more certain that she needed to use her experience to help others.
Soltys was also inspired to share the knowledge she has gained through trial and error.
“We have had to do a lot of research on our own throughout this journey,” she says.
“Figuring out ways to cover treatment costs while being out of work, learning about alternative treatments – the disease itself is really difficult, but it doesn t have to be as difficult with the options that are out there.”
Soltys, Bennett and Coleates are now in the process of starting a foundation to help individuals with terminal diagnoses.
“We want to teach people that cancer doesn t have to be a death sentence,” Bennett says. “It’s something you can live with and have a good quality of life.”
“If you see a shooting star, you want to share it with someone,” Coleates wrote in an email to PEOPLE. “I feel like I am that shooting star, and I need to share my story and what I have learned with everyone so they can be brought into the light.”