Kids get minor illnesses fairly easily, so when Nicole Defeo Campbell's son Nathan wasn't feeling well, she thought it was just a cold. One day, he went to the nurse's office at his school where he's in kindergarten to get a routine check-up, and a perceptive nurse knew something was terribly wrong.

First of all, Nathan refused to go outside and play with the other kids because "his leg hurt."

While most people would dismiss the boy's pale complexion and body aches as a cold or fever, the New Jersey nurse Patti Butler had seen the symptoms before and she knew what they meant.

Patti called Nathan's mom to advise her to take her 5-year-old son to a doctor immediately.

"His skin was translucent, and that's when I said I've only seen someone look like this color once in 25 years," Butler told CBS.

Her quick thinking saved Nathan's life, because his translucent skin and bruising turned out to be the first signs of the deadly cancer Leukemia.

Nathan's mom didn't heed the seriousness of the nurse's warnings at first and thought she was being paranoid.

"Honestly, I wrote it off," Nicole Campbell said. "I really thought she was being kind of alarmist because I didn't see anything wrong with him, and then the doctor himself called."

Nathan was admitted to the Children's Hospital of Philadelphia for treatment. Six months later, his cancer went into remission and he's recovering well.

In thanks for saving her boy's life, Campbell nominated Patti as America's Greatest School Nurse.

"If it weren't for Patti pushing as hard as she did, I don't know that my son would be here," Nicole said in an interview with the Courier-Post. "That's the honest-to-God truth."

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