Teen asks his terminally ill sister, 10, to high school formal

Ten-year-old Rebekah Spader is your classic girly girl. She enjoys dressing up and playing with makeup. But there's only so much time for fun when you're battling a terminal illness.

Courtesy of Stephanie Spader
AJ and Rebekah Spader on the night of the formal

Rebekah was born with HSAN, a heredity disorder that attacks the nervous system, and was diagnosed with MDS, a blood disorder, six years later. Her parents were counting on a bone marrow transplant she received four years ago to be her saving grace. Sadly, it wasn't.

Still, thanks to her big brother, AJ, Rebekah finally had the chance to get all dressed up with somewhere to go: O'Gorman High School's Valentine's Day formal.

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"She probably won't be able to experience a dance herself, so I wanted to make sure she did," AJ, 15, told "I also want to spend as much time with her as I can."

Courtesy of Stephanie Spader
Rebekah dressed for the formal in a sequined dress with a tiara that made her feel like a princess.

Her mom, Stephanie, and grandma, Sue Peters, did Rebekah's hair and makeup. Then she slipped into her sequined navy blue dress and donned a tiara, making her feel like a princess.

Peters' house in Sioux Falls, South Dakota, quickly filled with six high school freshman and their parents, who couldn't snap enough photos. They ate pizza and planned to head to the dance, but Rebekah was just not feeling up to it.

Courtesy of Stephanie Spader
AJ with his friends and sister Rebekah on the night of the formal

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"Since she was in the hospital three days prior, we weren't surprised she didn't make it to the formal, but she sure enjoyed getting ready and had a blast at dinner," Rebekah's father, Tony, told "AJ still ended up going to the dance, though, and is happy he did."

"It was so special to have her [at the party], and my friends had a ball with her too," AJ said.