It has robbed her of meeting milestones and being able to make friends or keep up with other toddlers her age. It has paralyzed her from the chest down, with doctors saying she would never walk.

As she gets older, Zéa is realizing that she's different. While wearing ballet slippers, the little girl who loves to bop around to music looked at her mother and said, "My feet are broken, Mama."

But Zéa -- with the help of her family, doctors and a variety of physical therapists -- has overcome tremendous obstacles just to live.

'Covered with cancer'

Zéa was a happy, healthy baby for the first few months of her life in Miami. Then, she started running a fever that spiked to 106 degrees by the time she arrived at the hospital. It was the only sign that something was wrong.

The hospital staff ran every test imaginable. An MRI revealed the truth that her parents had not dared to imagine.

"She was covered with cancer," said her mother, Heather Lane. "She had a primary area on her spine, and from there, she had disease that had spread to her liver, lungs, kidneys, bone marrow, even in her skull. We nearly lost her at that point."

They had never heard of neuroblastoma , a rare cancer that largely affects very young children. There are about 700 cases a year in the United States, accounting for 6% of cancer in children, according to the American Cancer Society.

While Zéa was still sedated, her parents had to make a choice within 15 minutes: major surgery to remove the tumor or begin chemotherapy immediately.

The neurosurgeon and the oncologist didn't agree. It was up to her parents. They opted for the surgery.

"The tumors were compressing her spine, and it had deviated her spine to the point where they were worried she would be permanently paralyzed for life," Lane said.

After the surgery, Zéa became paralyzed from the chest down.

Two days after her surgery, Zéa began her first cycle of chemotherapy. She would undergo eight total, staying in the intensive care unit for weeks.

The surgery was tough on Zéa, but it was nothing compared to the chemo. Each round contained four types of chemotherapy "cocktails," all with different side effects, and she handled some better than others, her mother said.

Some of them would wipe out her immune system to the point where she needed blood transfusions. Her mother lost count of how many Zéa had.

"Every time she would get another dose of chemo, I literally watched the life slip away and return," Lane said. "She turned gray. And then when she would have a blood transfusion to bring her counts back up, then the life would literally come back. It was incredible."

Hope and help

After Zéa completed her eight cycles of chemotherapy, her doctors in Miami wanted her to undergo four more.

When Zéa had surgery to remove her primary tumor, they were forced to leave behind a tiny sliver that remained between her spine and lungs. Bundled among her nerves, the piece could cause damage. Removing it could cause Zéa to lose all movement of her right arm.

Her parents decided to seek a second opinion. They took her to Memorial Sloan Kettering Cancer Center in New York.

Her oncologist at Sloan Kettering, Dr. Shakeel Modak, specializes in neuroblastoma. He told the Lanes he wanted to keep Zéa on a "watch and wait" protocol, with no more plans for treatment unless things changed.

He has treated patients with this rare combination of neuroblastoma and paralysis, but it's so rare, there are only about 20 cases per year in the US.

"My job was to make sure we didn't give her too much treatment, which would lead to other long-term complications," Modak said. "Giving a very young child chemotherapy radiation can be lethal."

For reasons that doctors don't understand, when neuroblastoma occurs in very young children, the tumors can resolve on their own and shrink. In Zéa's case, this occurred after her chemotherapy.

The sliver has been inactive on scans during Zéa's last three appointments with Modak over the past year. And even better, it's shrinking. It could become scar tissue, but just to be sure that the small chance of recurrence doesn't happen, they monitor her closely. She is now considered stable.

While Zéa was fighting cancer, the damage it left behind on her spine seemed irreversible.

But her parents had hope when they saw her wiggle her toes for the first time after the chemotherapy was completed. The paralysis wasn't permanent, as they had feared.

Modak wanted to help. He recalled a young patient in a similar situation he had treated years before; her determined mother was able to find help at the pediatric International Center for Spinal Cord Injury at the Kennedy Krieger Institute in Baltimore.

There was a chance that because Zéa was still a very young and developing child, therapy and rehab could turn the wiggling of her toes into walking. It wouldn't work for an adult, but children have a plasticity at that age that makes it possible, Modak said. Within a month, Zéa was put on a rehabilitation program at Kennedy Krieger.

Zéa working on her aquatic therapy.

Learning to walk

Zéa connected with her therapists, Paige Bourne and Rachel Mertins, right away, Lane said. Bourne is her physical therapist, and Mertins oversees her aquatic therapy.

"I just fell in love with her attitude and her energy she has," Mertins said. "She loves to play, and she works really hard."

The pools at Kennedy Krieger are special in that hydraulic lifts can raise or lower the floors, enabling their youngest patients to move in dynamic ways on underwater treadmills. In the water, Zéa can learn to move in different ways without gravity restricting her.

It also removes the fear of falling and eases movement, as opposed to harnesses that can make movement even more difficult.

"The pool is where they can be a little more free and independent," Mertins said. "By putting her in water, everything is easier, becomes more buoyant and more successful, which means it is more likely to carry it over to land."

Zéa began learning to walk in water, building up muscles and strength with floaties on her arms and the steady hands of a therapist on her waist.

She goes for two-week sessions every few months. Zéa has therapy for three hours a day, which is intense for a toddler, but she works hard and handles it well. Her therapists are used to working with kids, so they make sure she takes rest or snack breaks or even a short visit with Mom, when she needs to.

But they also push her when she needs it most, her mother said.

Mertins and Bourne said Zéa has made tremendous gains since her first session in January. Then, she was working on developmental milestones like kneeling and crawling, with a little bit of standing and walking.

In May, she came back stronger. Zéa walked on the aquatic treadmill without support for her arms and walked for longer distances using the assistance of a walker on land.

Her therapists send Zéa back to Miami with a customized home program to work on with her local physical therapist in between sessions. Zéa's parents also work with her at home on using the walker.

They take her to hippotherapy once a week at Bit-By-Bit, a local nonprofit therapeutic horseback riding center. The 30-minute sessions riding a short horse named Gypsy Gold provide a fun activity that helps her increase strength and balance, since the horse is constantly in motion. Her therapists at Bit-By-Bit say Zéa has shown great progress in mobility and trunk strength.

Zéa uses a walker at home between sessions.

Zéa returned to Kennedy Krieger for her third session in October.

"Zéa continues to make impressive gains," Bourne said. "She is walking more independently and further every session. As she's growing up, she's more engaged in physical therapy and is motivated to work hard to reach her goals."

"I saw Zéa for the first time in five months in the pool and noted improved strength, core stability and gait endurance," Mertins said. "In the pool, she was able to walk for longer periods of time on the underwater treadmill with only very minimal assist from me and no upper extremity support!"

Zéa's right leg is weaker, so they try to get her to lead with that leg during exercises. But they aren't the exercises you imagine for a physical therapy session. Usually, there is a toy nearby that Zéa is trying to reach.

During one session, Bourne had Zéa use a modified Ride On four-wheel car that is triggered to drive when she goes from sitting to standing. She took one lap around the gym and then asked her mom for sunglasses and a purse so she could drive with them.

"With a kid who is 2, it's about making things functional and also fun and making sure they are really engaged in the therapy," Bourne said. "It's play and hard work."

Zéa uses assistive devices to move around.

A fighting spirit

Her doctors, therapists and parents are all confident that Zéa will continue to improve and move more independently. As she achieves more milestones, Mertins believes, Zéa could also learn to swim.

"Swimming is a way she can interact with friends and give her a jumpstart in this world where she is constantly struggling and or maybe feeling left behind a little bit," Mertins said.

"I just hope she is able to play with kids her age and move around, especially when she starts school independently, and just being able to do any of the activities that a typically developing kid could do," Bourne said.

The Lane family is willing to travel so that Zéa can have these opportunities. They were on a wait list for eight months at a local therapy facility. Though Zéa's dad still works, Lane was let go from her job shortly after Zéa was diagnosed, and she said that a variety of cancer foundations make the travel possible. Angel Flight provides certificates for air travel through JetBlue for cancer families. The Ronald McDonald House helps with accommodations in Baltimore and New York.

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They are assisted by local groups in Florida and New York, as well as their community. The family has also started a nonprofit, Whimsy World , an art therapy program for children with cancer in hospitals.

Everyone who meets Zéa falls in love with her fighting spirit and sassy personality, her mother said. Her 10-year-old sister, Kaia, calls Zéa "sweet with a sprinkle of spice."

It's that spirit that has helped Zéa accomplish so much, and it's why she won't back down even when therapy gets tough.

"As far as her walking independently, I am hopeful she will get there," Lane said. "But we have reached so many goals they have put in place for her. Zéa was not even able to sit up on her own after surgery. She wasn't able to roll over for many months, wasn't able to crawl. I never thought that she would. I was preparing myself for dealing with a child that could potentially be paralyzed from the chest down. But she just keeps beating the odds."