Maryann Oakley and her husband Nathan knew from the start that their daughter Eve Elizabeth would be a fighter.
The toddler was initially thought by doctors to be a “vanishing twin,” a sac of cells soon to be re-absorbed into her mom’s womb while her fraternal twin sister Ella Rose took over the real estate.
The now-2-year-old girl managed to push through that — but what her parents didn’t know was that Eve and Ella would have to put up an even greater fight, all before their first birthday: the same life-threatening eye cancer.
“We’ve been through too much,” Oakley, 40, tells PEOPLE. “And the twins, more than some will endure in a lifetime.”
Both Ella and Eve are battling Retinoblastoma, a rare eye cancer that affects just 250-350 children each year in the United States, according to the U.S. National Library of Medicine.
The toddlers’ heart-wrenching medical history began just 10 days after their birth in December 2017, when Eve was first admitted to the hospital near the family’s Pennsylvania home for what turned out to be a potentially life-threatening twisted bowel.
Before she’d even been able to celebrate two weeks with her daughters, Oakley watched as little Eve went into cardiac arrest, then septic shock due to a leaky intestine, and finally, was put on life support for more than a week as her kidneys and liver started failing.
“I was screaming in there, like, ‘She was fine!’” Oakley recalls of the terrifying decline in her daughter’s health. “It was just, everything changed so fast. We had no idea if she was going to pull through.”
The bad news would continue to snowball for the family of four.
While on life support, Eve had her eyes scanned, and after a mysterious white fog hinted toward Retinoblastoma, Oakley and her husband decided they needed to check Ella for the disease too, “just to be safe.”
“They found two tumors, one in each eye,” says Oakley, who at the time was on maternity leave from her job as a therapist for adults with autism. “And I’m like, ‘What the hell is going on?’ I have one child on life support, one is getting diagnosed with cancer.’ So then we knew Eve had it, too.”
Ella, just two weeks old, was started on chemotherapy two days later at the Children’s Hospital of Philadelphia, while Eve remained on life support two hours away at the Hershey Medical Center.
“You pretty much just go on Auto-Pilot, that’s the only way I can explain it,” says Oakley. “It’s just bad news after bad news. You just pray, standing outside for a breath of fresh air, just praying, like, ‘Let Eve live. I don’t care if she has brain damage. Just let her live, please.’ My mom passed away of uterine cancer shortly before they were born, so she never got to meet them. But I was already through that once. I was like, ‘Please let this child live.’”
Shortly after Ella’s diagnosis, Eve was transferred to CHOP, too, and once she was taken off life support, began her six rounds of chemotherapy along with her sister at the nearby Wills Eye Hospital.
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For Ella, the treatment was partially successful — doctors were able to laser out the tumor from one eye, though it remains in the other. Eve, meanwhile, still has her one tumor in her eye.
The girls currently get scanned for new eye tumors every three months, as their risk of tumors will only decrease once they’re between 3 and 5 years old.
“I’m just kind of waiting until it’s going to happen again,” she says of her daughters’ eye tumors. “I hate thinking like that, but maybe at the same time it prepares myself, I don’t know. We’re just waiting.”
They also get checked every six months for Trilateral retinoblastoma, which can develop on the brain’s pineal gland and can prove fatal.
And that’s not all — as a result of the drug used to save Eve’s life when she went into cardiac arrest and septic shock, the toddler has now also been diagnosed with the hearing disorder auditory neuropathy, something Oakley says initially put her in a state of denial.
“We’re working on sign language, she says. “We’re working on that to see if she’s going to need hearing aids… She also has high blood pressure, and they think that was because of the kidney failure.”
Oakley says you wouldn’t know what the “laid-back” and “happy” girls — who now receive various types of therapy, including hearing, speech and physical — have been through based on their bubbly personalities.
“I call Ella the alpha of the house, she kind of takes over,” she says. “They love when people come over, their therapists come over, and they just love hugs and sitting on their laps and smiling and laughing.”
Her daughters are also huge fans of Ellen DeGeneres, and ask mom to put on her talk show each day when they wake up from their naps.
The girls’ medical woes have put a financial strain on the family, as Nathan, 33, has been working three jobs to support their medical bills while Maryann stays at home with Ella and Eve.
A GoFundMe page for the family has so far raised more than $25,000 over two years.
“Our lives are pretty much turned upside down emotionally, financially, physically,” she says. “Yes, they’re doing well now, but we constantly have anxiety of when the cancer is going to come back and [whether] Miss Eve’s going to be okay with her hearing and her bowel.”
The family’s dreams of bringing the girls to California and of moving out of their two-bedroom condo have been put on hold as they pour their energy into medical care and transportation down to CHOP, which is about two hours away from their home in Harrisburg.
Still, the mom says the girls — who were recently featured on Kristen Bell’s Instagram page — are “the best things that ever happened to me.”
“I love sharing their story,” she tells PEOPLE. “I hope one day that they can go on and do the same thing.”