Save lives like Rihanna: Become a bone marrow donor

Today, you can save a young girl's life with just a swab of your cheek.

When Shannon Tavarez was just 11-years-old she already had a  promising Broadway career, performing four shows a week as young Nala in "The Lion King."

Now Shannon's dream is simply to grow up. In April she was diagnosed with Acute Leukemia. The symptoms hit when she was onstage. Her lower back and legs suddenly started hurting making it hard to walk.

"When I found out, it hit me really hard ... It was shocking and I thought, why me?" says Shannon, who is now getting daily chemo treatments at Schneider Children's Hospital in Long Island. Doctors say that a bone marrow transplant is her only hope.