In September 2014, when she was just eight years old, our daughter Elise was diagnosed with osteosarcoma, a type of bone cancer. It was in her right leg. Part of her treatment involved a surgery called a “rotationplasty,” which my husband and I had never even heard of prior to coming to MD Anderson.

Here are five lessons we’ve learned since then — about rotationplasties, sarcoma and life in general.

Realize kids see things...