Homecoming Queen Has a Rare Skin Disease That Makes Her Severely Allergic to the Sun

Riley McCoy, 17, could get life-threatening third-degree burns if she's exposed to ultraviolet rays.

A California high school senior who is allergic to the sun has traded her ultraviolet ray-blocking mask for a tiara as she was crowned homecoming queen.

Read: Woman Kisses and Cuddles Daughter to Let Others Know Her Skin Disease Isn't Contagious

Riley McCoy, 17, appeared in front of classmates at Dana Hills High School during the Friday night ceremony to accept the honor in a sleeveless blue gown — a rarity, considering she would get severe burns if she were exposed to sunlight.

“So many people voted for me," Riley told KTLA. "I had great support. I’m super happy and thankful and blessed.”

McCoy was born with xeroderma pigmentosum, a rare skin disease that puts her at risk of third-degree burns or even death when exposed to sunlight.

“She slowly lost her hearing; she wears hearing aids,” her mom Pam McCoy said. “It has affected her speech, it affected her gait."

Riley goes to school every day in a NASA-approved UV-blocking mask that covers her head, face and neck. She also covers her arms by wearing long gloves.

“I was really worried when she came to school it was going to be a rude awakening and that there was going to be bullying,” her mom said.

Read: Baby with Rare Skin Disease Defies Doctor Predictions by Walking, Talking and Living Past First Birthday

But as Riley got on stage to accept the honor, Pam said she couldn’t start crying and was moved by how much support her daughter received at school.

"I got a lot of encouragement," Riley said. “I’m very thankful and very blessed to have people in my life and friends.”

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