BORN WITH A GIANT BIRTHMARK, BABY LIVI’S FAMILY FACED A TERRIFYING DISCOVERY INSIDE HER BRAIN

A Birthmark That Covered Much of Her Tiny Body

When Olivia “Livi” Sheahan was born in May 2025, her parents, Harmonie and Jason, were excited to welcome their long-awaited baby girl. But the first moments after her birth quickly became frightening when they noticed a large, dark birthmark covering much of her body.

The mark stretched from her chest and back down to above her knees, with smaller marks scattered across her face and other areas of her skin. Doctors took photographs to examine the unusual pigmentation, and the family began searching for answers.

A dermatologist diagnosed Livi with a giant congenital melanocytic naevus (CMN), a rare condition involving an unusually large collection of pigment-producing cells in the skin. The family was also told that, in some cases, the condition can be associated with changes affecting the brain or spinal cord.

The Scan That Initially Brought Relief

When Livi was about one month old, she underwent an MRI. Her parents were relieved when they were initially told that the scan appeared clear. They hoped the birthmark would be a visible skin condition rather than something more serious.

That relief did not last. At around three months old, Livi began crying persistently and experiencing projectile vomiting. Her family rushed her to hospital, where doctors discovered hydrocephalus—a dangerous buildup of fluid in the brain.

Livi underwent emergency surgery to have a shunt inserted to help drain the excess fluid. She survived the operation, but further investigations brought another difficult diagnosis.

A Rare Neurological Diagnosis

Additional testing, including a contrast MRI, revealed that Livi had neurocutaneous melanocytosis (NCM). According to her mother’s account, specialists explained that pigment-producing cells associated with the condition had also affected areas inside Livi’s brain and spinal cord.

Genetic testing identified an NRAS mutation. Her family was told that the disease could continue to progress and that there was no cure available at the time described in the report.

The diagnosis changed what her parents had understood about the birthmark. What had first appeared to be a difference on the surface of her skin was connected to a much more serious medical challenge.

More Surgeries and Ongoing Treatment

Livi’s medical journey continued through her first year. At five and a half months, her first brain shunt failed and had to be replaced. At seven and a half months, fluid accumulated in another part of her brain, requiring another operation and an additional shunt.

When Livi was nine months old, she began ongoing chemotherapy intended to slow the progression of the disease. Her mother described the treatment as difficult, with vomiting and periods of persistent crying. The treatment schedule included daily oral medication and injections over seven days in each 20-day cycle.

These experiences placed enormous emotional pressure on the family. Her parents had to balance work, hospital appointments and concerns about infection because treatment left Livi more vulnerable to illness.

A Little Girl Still Finding Reasons to Smile

Despite the surgeries and treatment, Livi’s mother said her daughter continued to smile, laugh, crawl, pull herself up and babble. By the time of the family’s first-birthday celebration, the birthmark covered around three quarters of her body.

Friends rallied around the family, including organising a fundraising running event to help Livi’s mother take time away from work and spend more time caring for her daughter.

Livi’s future remains uncertain, and her family continues to take things one appointment and one day at a time. By sharing her story, her mother hopes more people will understand that a large congenital birthmark can sometimes be associated with serious underlying medical conditions—and that families facing rare diseases need support, research and hope.

Source: that’s life!, “It’s just a birthmark: The rare disease hidden inside my baby’s brain,” June 19, 2026.