A mum fears people will think her baby is "dirty" after a rare skin condition covered her tot's back in a giant birthmark.

Two-month-old Macey-Mai was born with giant congenital melanocytic nevus (GCMN), a benign, tumour-like malformation resulting from faulty development of pigment cells.

Her mum, Katelyn Clarke, 23, said nothing was detected at her ultrasounds until she gave birth to the tot naturally on May 7, 2025, at University Hospitals Plymouth, weighing 5lbs 15oz.

Katelyn and partner, Dainen Milne, 23, were "completely shocked" when medics spotted the dark mark covering her entire back – as well as the sides of her stomach, scalp, legs and arms.

A dermatologist diagnosed Macey-Mai with GCMN on May 9 and the family were referred to a GCMN specialist at Great Ormond Street Hospital (GOSH). The skin condition – which also causes benign tumours to grow – means the delicate skin on Macey-Mai's back is "constantly" bleeding. To avoid the skin tearing, the tot has to be dressed in bandages daily and lie on her stomach at all times.

Katelyn and baby Macey-Mai, in hospital. A mum fears people will think her baby is "dirty" after a rare skin condition has covered her tot's back in a giant birthmark that is "constantly bleeding" Two-month-old Macey-Mai was born with giant congenital melanocytic nevus (GCMN), a benign, tumour-like malformations resulting from faulty development of pigment cell. Her mum, Katelyn Clarke, 23, said nothing was detected at her ultrasounds until she gave birth to the tot naturally on May 7 2025, at University Hospitals Plymouth, weighing 5lbs 15 oz. Katelyn and partner, Dainen Milne, 23, were "completely shocked" when medics spotted the dark mark covering her entire back - as well as the sides of her stomach, scalp, legs and arms.
Katelyn and baby Macey-Mai, in hospital (Katelyn Clarke / SWNS)

While Macey-Mai will always have the dark birthmark, her parents are awaiting a surgery date to remove the benign tumours – which are causing the tot pain. The National Library of Medicine says the condition affects one per cent of newborns, with one in 20,000–500,000 live births being reported with GCMN. Katelyn, a full-time mum from Plymouth, Devon, said: "It was a complete shock because nothing had been detected. "Dainen and I were in utter shock.

"Since bringing her home, it's been very hard because she's in so much pain.

"She wears a bandage because her back bleeds and is crying all the time. Hearing her in pain breaks my heart.

"Looking at her, you'd think that it's dirt on her scalp and back, but unlike dirt, it's not removable. "I worry about explaining it to other people and about other kids commenting on it when she's older too.

"She'll have to live with this for the rest of her life."

Despite being at high risk of potential incompatibility from her rare blood type, Katelyn says she had a "straightforward pregnancy", with the couple sharing Callie, four, and Sonny, two.

"Macey-Mai was born full term, but she was tiny," Katelyn said. "She wasn't even placed on my chest because she'd swallowed some amniotic fluid. "She had to be put on oxygen immediately after being born. "But that's when medics saw the dark patches on her body. "When they broke the news and showed us, I couldn't speak.

"Our first thought was 'is our little girl going to be okay?'"

Katelyn and baby Macey-Mai. A mum fears people will think her baby is "dirty" after a rare skin condition has covered her tot's back in a giant birthmark that is "constantly bleeding" Two-month-old Macey-Mai was born with giant congenital melanocytic nevus (GCMN), a benign, tumour-like malformations resulting from faulty development of pigment cell. Her mum, Katelyn Clarke, 23, said nothing was detected at her ultrasounds until she gave birth to the tot naturally on May 7 2025, at University Hospitals Plymouth, weighing 5lbs 15 oz. Katelyn and partner, Dainen Milne, 23, were "completely shocked" when medics spotted the dark mark covering her entire back - as well as the sides of her stomach, scalp, legs and arms.
Katelyn and baby Macey-Mai (Katelyn Clarke / SWNS)

Macey-Mai spent six days in a neonatal intensive care unit – where she was diagnosed with GCMN on May 9 – before returning home on May 15.

The family have since been referred to a GCMN specialist at GOSH, where Macey-Mai has been assessed and given the prognosis of surgery to remove the tumours on her back. To help manage the pain and bleeding from the growths attached to the birthmark on her back, Macey-Mai is on painkillers and has to wear a bandage and dressing at all times.

The family are currently on a general waiting list for surgery to remove the growths and are awaiting a date.

Macey-Mai's birthmark will grow proportionally to her body, and after her surgery, she will need to have an MRI to check her brain and spinal cord to screen for neurocutaneous melanosis (NCM), a condition where melanocytic cells grow in the brain and spinal cord, causing neurological problems like seizures and vision problems. Katelyn has been told by medics that the tumours can grow back after surgery, but a biopsy will be sent off to be examined to check for melanoma.

Dainen and his older daughter. A mum fears people will think her baby is "dirty" after a rare skin condition has covered her tot's back in a giant birthmark that is "constantly bleeding" Two-month-old Macey-Mai was born with giant congenital melanocytic nevus (GCMN), a benign, tumour-like malformations resulting from faulty development of pigment cell. Her mum, Katelyn Clarke, 23, said nothing was detected at her ultrasounds until she gave birth to the tot naturally on May 7 2025, at University Hospitals Plymouth, weighing 5lbs 15 oz. Katelyn and partner, Dainen Milne, 23, were "completely shocked" when medics spotted the dark mark covering her entire back - as well as the sides of her stomach, scalp, legs and arms.
Dainen and his older daughter. (Katelyn Clarke / SWNS)

Katelyn said: "Having a baby is a full-time job, but I'm a round-the-clock nurse for Macey-Mai too. "She cries a lot because she's in so much pain. "It's upsetting to see, not just for us but her brother and sister. "Some nights Dainen and I sit and cry because we feel almost helpless. "Her surgery can't come quickly enough, but she'll have her dirt-like birthmark for life.

"Because of GCMN, she is at a higher risk of developing cancer, but I can't dwell on that too much because it makes me upset.

"I have to focus on caring for Macey-Mai right here and now. "She's the most precious little girl."

The family have set up a GoFundMe page to help with medical costs Macey-Mai will need now and in the future: https://gofund.me/38d8e9d4