Birthday wish of six-year-old battling cancer explodes as thousands send cards

Meet Danny Nickerson. He has a rare, aggressive form of brain cancer, and his story has inspired many. Today is his sixth birthday. His birthday wish? For you to send him a card.

Danny's mother, Carley Nickerson, posted on Facebook that her son loves receiving mail and that people should send Danny some birthday cards. Her little post snowballed into an Internet sensation, with thousands of cards being mailed to Danny from across the country.

Check out these heart-warming photos of Danny and his cards from his Facebook page, Danny's Warriors. Friday morning his mom posted a picture of Danny as a baby, saying, "Happy Birthday to my favorite person in this world, my very best friend, the person I snuggle into every night, my hero."

Here's wishing a happy birthday to Danny, and if you want to send him a card, his address is below.

Danny Nickerson
P.O. Box 212
Foxboro, MA 02035