As a child, Colleen McDonald, 43, practically lived outside and got plenty of sunburns.

"We never really thought about sunscreen or anything – going to the beach – and as I got older, I went to tanning beds," McDonald said.

Studies show early sun damage can lead to skin cancer, which McDonald knows all too well.

"I don't even remember how many biopsies (I’ve had). I've had five melanoma surgeries," she said.

A new study in the Journal of Pediatrics shows many children might be headed down the same path. Of 360 children in Massachusetts, only 25 percent used sunscreen regularly. Many were also getting too much sun.

"Nearly 50 percent of the teenagers, at age 11, reported having at least one episode of sunburn, and that's alarming," said Dr. Steven Wang, of the Memorial Sloan-Kettering Cancer Center in Basking Ridge, N.J.

Melanoma is the deadliest skin cancer, and one of the most common cancers for young adults.

Doctors advise people to have a skin exam at least once a year and look out for lesions that change shape, size or color or become painful, bleed or itch.

McDonald hopes her story will be a lesson for children to take the sun seriously. She suggests people use sunscreen, wear hats and never go into a tanning bed because they can't undo damage from the sun.

It's estimated there will be more than 76,000 new cases of melanoma diagnosed this year and more than 9,100 deaths.