Pakistan, July 2 -- Today is Amma's birthday, and as I sit down to write this, I find myself struggling, as I always do, to put into words something that has never needed words at all. There is a particular kind of love that does not announce itself, that does not perform itself, that simply exists in the way air exists, necessary, invisible, and everywhere.

That is what Amma is to me. People speak of the umbilical cord as something that is cut at birth, a clean and final severance that marks the beginning of a separate life. I have often thought that in my case, someone forgot to do the cutting. Some odd years later, it is still there, this invisible thread between us, carrying not nutrients now but something more essential, courage, co...