An adorable baby girl is at the center of a medical mystery.
Ten-month-old Addison Cox was born with Stage 4 skin cancer, a disease that normally occurs after prolonged exposure to the sun.
How could it happen to a newborn?
Believe it or not, doctors say it was passed on to her from her mother during pregnancy, something that almost never happens.
X-rays showed Addison's body is riddled with tumors, but you wouldn't know it to look at her.
Her dad, James Cox, couldn't believe it when doctors told him she had cancer.
James told INSIDE EDITION, "We were speechless. It was like getting a good punch in the chest."
Doctors say there have only been nine documented cases in the past decade of a mom passing on cancer to her baby.
Addison's mother Briana, a Phoenix, Arizona, police officer, who spent much of her time out in the sun, didn't know she had a relapse of previously diagnosed skin cancer until she collapsed a few weeks after Addison was born. The mom was diagnosed with Stage 4 melanoma.
No one suspected Addison had it too, until dark spots appeared on her scalp.
Radiologist Dr. Jeffrey Miller said her mom's cancer cells passed through the placenta to her developing fetus.
Dr. Miller said, "Once the tumor gets in the bloodstream, especially when a child is in utero, it can go anywhere and that's what happened to Addison."
Briana blamed herself for passing the cancer to her daughter, according to her friend Sarah Gasper.
"I think she was shocked, blamed herself. But she moved on. Like we all told her, it's not her fault," said Gasper.
Sadly, Briana lost her fight with cancer on February 12th, but her grieving husband is determined to do everything he can to help their daughter.
He takes her for a weekly checkup at Phoenix Children's Hospital where she's given an M.R.I. exam to monitor the growth of cancer tumors in her body.
Addison has been placed on an experimental cancer drug that her dad grinds up twice a day and puts in her favorite food.
James said, "The tumors have stopped growing and have even shrunk a little, which is exactly what the drug is designed to do."
Addison's official prognosis is bleak—eighteen months to two years. Despite the odds, her dad says she's a fighter
"I have hope. Guarded hope, but hope," said James.
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