My husband Jim has a litany of coincidences in his life. He will regale you with them if you but utter the word. His main source of income is the result of a coincidence; meeting an Oberlin college friend on the street in Manhattan and finding the friend had a bar for sale just as Jim’s profession as a news-film journalist was being eclipsed by television news-readers.

In our family, we call the moment that two cars traveling in opposite directions meet at the same time and place that a pedestrian is walking, “Jim’s law of coincidence.” We pronounce this phenomenon co-in-sigh-dence.

While I am devoted to my spouse, I don’t track the coincidences in my life. Yes, it’s true that my husband knew my mother for years before he knew I existed. It’s also true that his bar on Hudson Street was a favorite haunt of mine before we ever met. I dismiss these facts as everyday life in the great cosmos.

Still, there is one coincidence in my life I hold dear. It is the birth of my niece Viveca on my 50th birthday. I didn’t meet her until six years later, at her father’s funeral. At first sight, her likeness to me at that age was striking. Until that day, neither of us had known that our birth dates were a match. My brother Geoff and I had been on-again, off-again over the years. When he was sober, he was the sweetest, smartest man; when he wasn’t, he was self-destructive in the extreme. During a sober period he had met Viveca’s mother, Juliet, and they fell in love.

Juliet is a businesswoman with a strong work ethic, a sharp mind and an able wit who has built a comfortable nest for herself and her daughter in Brooklyn. Since I was a late entry into her life, she could easily have dismissed me as a reminder of a relationship gone sour. Instead I was welcomed, along with my husband and children, as family. Over time, we have come together in the kind of bond that was broken by my brother’s addiction.

Geoff had once told me that Juliet’s grandfather was Fiorello LaGuardia, the former Mayor of New York City. It was an interesting tid-bit but one I had no occasion to discuss with Juliet until recently, on Viveca’s 13th birthday, when her grandfather, Eric LaGuardia, was visiting from Seattle.

I have always known that my great-grandfather, John M. Morin, had served in Congress with Mayor (then Representative) LaGuardia. My uncle George Morin’s book, “Love and War As Never Before,” documents the attendance of the mayor at Representative Morin’s funeral in Pittsburgh in 1942. Beyond that, I knew little of their association.

I mentioned this minor coincidence to Eric LaGuardia at Viveca’s birthday recently. “Who is your great-grandfather?” he asked. “John Morin,” I replied. “John Morin!?” he gasped, “I see his name every day of my life!”

As it happens, John Morin and Fiorello LaGuardia were great friends. The reason Eric LaGuardia instantly knew my great-grandfather’s name is that the framed marriage certificate of Fiorello and his wife Marie hangs in Eric’s home. John Morin was Fiorello’s best man.

Since that conversation, Eric and I have corresponded. He sent me a copy of the marriage certificate and other memorabilia that mention my ancestors. My grand-aunt Rose Morin sent a sympathy card to the LaGuardia family when Marie LaGuardia died in 1984 that refers to Juliet. That means Rose knew Geoff’s future mate years before they ever met, which parallels in my mind the coincidental pre-acquaintance of my mother and my husband. I wonder, does this kind of coincidence run in families?