Two-year reunion: (L-R) McKinley, Lauren, Chloe and Ava beam together in a photo taken last week, two years after they met on the cancer wards at Johns Hopkins All Children's Hospital in Florida.
Beaming in gold tutus and headbands, these four little girls look like any other care-free four- and five-year-olds.
If it didn't say "SURVIVOR" on their t-shirts, you would be hard-pushed to guess that McKinley, Chloe, Ava and Lauren all endured and defeated something few of their peers have faced: cancer.
Chloe was diagnosed with lung cancer, which is incredibly rare in children. The rest with acute lymphoblastic leukaemia, the most common childhood cancer; one that is harrowing to treat, since it infects the immune system, according to the Daily Mail.
The four girls met by chance at Johns Hopkins All Children's Hospital in Florida in September 2016, when doctors gave them all pink tutus to lift their mood during their treatment to mark Childhood Cancer Awareness Month.
As the girls sat together giggling, someone took a photo.
A year later, in September 2017 they returned to celebrate their remission and remake that photo. And now, they are back, and visibly ecstatic at being healthy, something most take for granted.
According to doctors at All Children's, the girls have flourished as they have regained strength.
Ava, whose full name is Avalynn, is a huge Disney fan, and very artistic. Chloe loves T-ball and fishing. McKinley is a self-professed "girly" girl - she loves princesses, jewelry, dancing. Lauren loves talking about animals, and hugging everyone.
Speaking to DailyMail.com, Alyssa Luciano, whose daughter Ava was diagnosed with acute lymphoblastic leukaemia, said everything right now is "surreal".
"Once your child has cancer, it's hard to imagine a 'normal' life again. It's even more special when it's with her sweet friends that she grew close with while they were all so very sick.
"Most people dream of different days for their children like the first day of school or weddings. These are the days we've dreamed of."
Having all the other mothers, too, was crucial for the families to grapple with the painful circumstances, Chloe's mother Jacquie Grimes said.
ALL is a type of cancer in which the bone marrow makes too many immature white blood cells called lymphocytes.
They crowd out normal white blood cells, causing the body to have a harder time fighting infections.
According to St Jude Children's Research Hospital, ALL is the most common type of childhood cancer. Approximately 98 percent of children go into remission within weeks of starting treatment and about 90 percent of those children can be cured.
However, the treatment is gruelling.
Ava, Alyssa explained, was diagnosed in January 2016 at the age of two after she began limping and had unexplained fevers.
By May that year she was in remission. But the risks of recurrence after such a short bout of treatment are high. So her doctors kept her on chemotherapy for more than two years - a total of 848 days - to be sure that it was gone.
The nausea and nights on end at hospital were heart-wrenching.
Childhood lung cancer - pleuropulmonary blastoma - is incredibly rare, with just a 40 percent chance of survival.
There seems to be no rhyme or reason to who develops PPB. In many cases, there is no history of disease, or external factors that could increase their risk.
Increasingly, though, scientists are seeing a correlation between PPB and a specific inherited genetic mutation called DICER1. DICER1 is seen in 80 percent of PPB sufferers. It is also linked to ovarian tumours and very rare brain tumours.
Symptoms seem like any other illness at first. The child may experience stressful breathing, a cough, or a fever.
In Chloe's case, it was much the same. For the last four months of 2015, it seemed like she permanently had a fever, her mother Jacquie Grimes told DailyMail.com.
Every time they took her to the doctor, and every time she was put on antibiotics, with a vague diagnosis that it was probably a UTI (urinary tract infection).
But the fevers persisted and worsened, as did Chloe's grunting and wheezing.
Eventually, on Christmas Eve, as relatives arrived to celebrate, Jacquie noticed Chloe slumped to one side, weak.
"Something in my gut told me to take her to the ER," Jacquie said.
Once they arrived, a doctor ordered an ultrasound of her abdomen, which transpired to be the wrong place - but an accident led them to her lungs.
"As they were trying to hold her down and look at her abdomen, she was screaming, crying and kicking," Jacquie explained. "And the tech accidentally went too high with the wand, seeing a mass that immediately concerned her.
"She left the room and soon others came in with her to take a look. Quickly after, they brought in an x-ray machine of her chest. The tumour was so large it had collapsed her little lung. The grunting noise she was making for months was her bodies attempt to push air into that lung."
It was so baffling that the medical team rallied scores of doctors from their homes to listen to Chloe's chest, hear her symptoms, and examine the rest of her body.
As it dragged on, it became clear this was not going to be a quick in-and-out with antibiotics as per usual, and Chloe was admitted to the paediatric intensive care unit.
"She was on countless monitors. She was miserable. Then a doctor came in and broke the news, that they believed she had cancer."
Dr Charlie Moore, who treated all four of the girls, said Chloe's is one that baffles even the global medical community.
"PPB is very rare in children; so rare that there's an international registry to better define it," Dr Moore explains.
Chloe's recovery has been astonishing, he said, as has that of all the other girls.
"It's tough enough trying to be a toddler," he said.
"There's so much learning and environmental stimuli going on. When you throw in a cancer diagnosis and the treatments that are needed, they really can't understand what's going on.
"It's not like talking to an adult and saying 'Mrs Jones, I need to put a needle in your arm to draw some blood'. So we really rely on their parents to learn how to communicate with them. And it means, children with cancer often mature much faster because they're thrown into a world where they have to learn so much about the real world.
"These girls were able to have a unique bond in that their peer group wasn't in the play ground, it was in the hospital and the clinic.
"It's been an absolute joy to see them grow and to see them outside of the hospital setting, being the kids they should have been all along.