I am an heir.

This is something of a sudden realization, although hints of it have been coming since about a decade ago. Back then my father was a mere 84 and my mother 31/2 years younger. Now he is about to be 94 and she is coming around the corner of 91, and when I mention these numbers to anyone, I almost always get the same response: Lucky you. You have inherited great genes.

This is my inheritance -- maybe not in itself better than money, but not something to be dismissed either. These genes to which I and my sister are the sole heirs have got to be sturdy indeed. In my mother's case, they overcame a childhood spent in Europe, in the Poland of World War I and the war with Russia that followed.

She was raised without a father, who was already in America waiting for World War I to end so he could send for his family. All the things kids are supposed to eat, my mother did not eat. The idea of a balanced diet was a joke. No fruits. No vegetables. On a given day, a potato was the whole meal. And even after her mother was able to bring her to America, she lived in poverty.

Yet now she walks her daily two miles or so, volunteers at the local hospital's gift shop, operates the phones at the assisted-living facility where she and my father live -- and takes care of my dad, which is no easy job.

As for my father, he was raised in a tenement on the Lower East Side of New York -- bad air, bad food, bad examples all around. He was orphaned at an early age, raised in an institution and sometimes farmed out to foster parents who, in some cases, treated him like dirt. He had a tough, unhappy childhood.

"Ask your dad about the [orphan] home," his lifelong friend once suggested, hinting at something ominous.

"What should I ask him about?" I asked. "I've asked him many times. What? What specifically?"

"Just ask," my father's friend said.

And so I did -- again. And again my father told the same old stories -- nothing bad, nothing awful. The bad, the awful is in him, like the genes people keep mentioning, somewhere deep and buried. Maybe it is better that way.

What occasions this column is, as you may have guessed, my father's 94th. I have written about him several times over the years, each time thinking it would be the last. Those genes, though, had other ideas. He has had it all -- heart problems, stomach problems, broken bones and stuff I'm sure he never mentions.

But he takes his walker and shuffles his way down the hall to some lecture or another -- maybe something about American history or politics or Judaism. Still learning after all these years. That's not a gene. That's his indomitable thirst for knowledge, the bar he keeps setting higher and higher for his son.

My father wanted to be a journalist. He told me that recently. He took a course at night, but he had no college education and the Depression was on and so he stayed with the job he had. He stayed with it until he retired -- a job, not a career. He marveled at the term "job satisfaction." To him, to his generation, it was satisfaction enough just to have a job.

People ooh and aah when I tell them about my parents. They pat me on the back, as if I have achieved something. The truth, of course, is that old age is precisely the shipwreck Charles de Gaulle said it was. At 94, you're on the reef, being pounded by infirmities, your body going overboard. Each day is hard for my father -- hard. But he is who he is -- maybe toughened by the orphan home, the foster homes, the Depression. He persists. He does not give up.

Now, back to those genes. People envy me for them, but the truth is I don't know whether I have them or not. It is enough that my parents have them -- that I am past 60 and they are still with me. It is a bountiful inheritance to be my age and still have the nagging obligation to call home, to wonder what he will think of my latest column (she only praises), to observe myself by observing him -- to be my age and still be loved as only a parent can love a child.

I am the richest of heirs.

Happy birthday, Dad.