Luna loved to twirl, jump, and dance from morning until bedtime.

One afternoon, she suddenly stopped and gently placed her hand on her side.

"Daddy," she said, "my side feels different today."

Dad gave her a hug and carefully felt the area she pointed to.

"I think it's a good idea to have a doctor take a look," he said. "Doctors are wonderful helpers, and we'll figure this out together."