When I was going through my medical training, one of the senior clinicians I most admired made a point to teach us how much doctors can learn from their patients. I can think of no better exemplar of that than today's bonus episode of Theory and Practice, where we talk with Julia Vitarello, the mother of a child with a rare genetic disease.

We first shared Julia's daughter's story a few weeks ago in our interview with Dr Timothy Yu about the first "N of 1" drug trial. Tim recounted the journey in developing her treatment, and the intellectual and operational challenges that he faced in order to find a therapy and get it approved. Today we hear Julia's perspective, as a parent who desperately looked for ways to help her child, Mila. All too often in these cases, there are no readily available therapies, and most patients don't have the benefit of extraordinary physicians like Tim, who refuse to accept conventional wisdom about what's impossible.

One of the things that I find so moving about this story is the heroic love and courage that pushed Julia and Tim to create not only a new therapy, but a whole new therapeutic regime. In their efforts to help Mila, they succeeded in creating an entirely new pathway that other patients can now start to follow. Therapies for previously untreatable diseases suddenly are possible, an incredible legacy for Mila and her family to give to the world.