We were just one family that had been struck by this disease; there were so many others. At that time many of them–most of them, actually–suffered silently. They were embarrassed by an ailment that relentlessly burns through the one thing we all rely on to define us–the mind. Who are we if we can’t recall who we have been, what we have done and learned? If we can’t think back on triumphs, defeats, sad times and bright days when joy lifted us off the ground? If we can’t look into the face of another and read all our history with that person?

Ten years ago, we didn’t know the answers to any of these questions. We don’t have easy answers now, but we are more comfortable with the questions. What my father did with his letter–and he knew he was doing this–was to lift a shadowy veil from a disease that people were ashamed to discuss.

We didn’t know as a family what to expect. No one could tell us–not really. Doctors gave out little pamphlets that didn’t help very much–clinical explanations and dire predictions. The stages of the disease were numbered, as if Alzheimer’s followed a map, a paint-by-numbers pattern. As if it had some kind of protocol to it. My family learned what other families have learned all too well: there is nothing predictable about Alzheimer’s. It claims every individual differently. Sometime in the past 10 years, a saying has evolved about the disease: if you’ve seen one person with Alzheimer’s, you’ve seen one person with Alzheimer’s.

In some ways, we were lucky. My father never had episodes of violent frustration, although it’s understandable that many people do. Memories are being incinerated, turned to ash and dust. There is no cure, no medicine to vanquish the vanquisher. Alzheimer’s always wins in the end.

Yet here we are, 10 years after my father wrote his letter. Alzheimer’s is no longer spoken about in whispers. There are organizations; there are deep, helpful, true stories that families can learn from. And there is the very real promise of a cure. In 1994, if you had heard the words “stem-cell research,” you’d have been puzzled. You would probably have had no idea what it meant, unless you were a scientist and particularly well informed. Now, in 2004, it is the miracle that can cure not only Alzheimer’s but many other diseases and afflictions. Now, in 2004, my mother has emerged as a central figure in the effort to get the federal government out of the way. If that phrase about the government sounds familiar, it should. I grew up hearing my father say often that the government should get out of the way.

I also grew up hearing my father say that everything happens for a reason, even if we don’t know what it is. “God has a plan,” he always said. “And God does things in his time. It’s always right even if it seems a mystery to us.”

Until my father’s death on June 5, I had no idea why God would have wanted him to last so long with a disease that stole so much. Why did his soul have to linger in a body and a mind that had been so cruelly conquered? Why did my mother have to go through year after year of drawn-out loss?

I think I know now. And I think my father is smiling and saying, “I told you there is a reason for everything.” Because my mother now has a chance to make a contribution to this country and this world, arguably as important as those of my father’s. She is the voice for stem-cell research now. But she found her full voice only recently; it was just a few weeks ago that she was publicly honored for her efforts–an honor that placed her firmly at center stage.

It has also placed her firmly against the White House–at least those currently in residence there. I swear I can hear my father chuckling at that.

Just as she believed in him, I think in his soul he believed in her enough to linger here in this world–long enough for her to step forward, long enough for her to accept that she has an important role to play even after he is gone. Although, of course, he isn’t really gone; the crowds and the outpouring of love and reverence have proved that. He lives on in this country and in this world. He lives on in people’s hearts and minds and memories. Most of all, he lives on in my mother.

Many years ago, my father sat in a jeep on a mountaintop at his ranch, giving an interview to Mike Wallace. He talked about the importance of serving. He said there is no higher calling. He believed that. He got it from his mother–a woman whose sweet, uncomplicated faith inspired the same in her youngest son.

It’s been 10 years since my father was diagnosed with Alzheimer’s. He will be known for many things, among them the uncomplicated way he shared his diagnosis with America and the changes his disclosure set into motion. Ten years from now, when stem-cell treatment makes Alzheimer’s and other diseases curable ones, my mother may very well be known as the person who stayed behind after the love of her life left… because it was her time to serve, her time to leave something behind that would change lives for all the years to come.