‘Like Family’ by Paolo Giodano

Meredith Sadler for the boston globe

They mean the nickname fondly, but there's a whiff of condescension about it, and the strong scent of self-flattery. The couple at the center of Paolo Giordano's spare and ruminative third novel, "Like Family," call their little boy's nanny Babette, after the heroine of "Babette's Feast."

You remember "Babette's Feast," don't you? In the short story by Isak Dinesen and the Oscar-winning 1987 movie Gabriel Axel made of it, a widowed Parisian refugee flees to the home of a pair of poor Norwegian sisters, bearing a letter of introduction that vastly underplays her culinary artistry ("Babette can cook") and beseeches them to take her in. "If they sent her away she must die," Dinesen writes.

The widowed nanny in "Like Family," who is otherwise known as Mrs. A., is in no such desperate straits when she arrives to join the household of Nora, a decorator, and her callow husband, a physicist who is our nameless narrator. The book begins with the news of Mrs. A.'s death, on the physicist's 35th birthday, but it was not they who sent this indispensable older woman away to die.

After eight years in their employ, beginning as a housekeeper when Nora was put on bed rest while pregnant, then later as a nanny after the birth of baby Emanuele, Mrs. A. chose to leave, suddenly too weary to continue. With her departure, a pampered pair of adults who have always been daunted by the notion of running their own household — who have seemed, in a way, to be playing at grown-up things like marital love and commitment — are abruptly left unchaperoned.

"Mrs. A. was the only real witness of the enterprise we embarked on day after day, the sole observer of the bond that held us together," the physicist muses, unable to divine instructions for his marriage from Mrs. A.'s reminiscences of her own. "In the long run, every love needs someone to witness and acknowledge it, to validate it, or it may turn out to be just a mirage. Without her gaze we felt at risk."

Giordano, whose first novel was the international bestseller "The Solitude of Prime Numbers," writes in a style so cool and clean that it can verge on the clinical. "Like Family" unfolds in northwestern Italy, not far from France, but it has an almost Nordic chill — apt for a novel that nods to both Dinesen and to Henrik Ibsen.

Ibsen's Nora, in the play "A Doll's House," also loses the principal witness to her marriage, a family friend who sequesters himself to die. That Nora famously walks out at the end, leaving her husband and children behind. I read "Like Family" wondering whether the same thing would happen here.

Giordano's novel invokes the sacredness of family, though its Nora and her husband like to keep their distance from blood relations. Mrs. A., whom they prefer, considers these two "her adoptive children," and while young Emanuele has a complement of ready-made grandparents, he and his nanny seem to share the sweet belief that she also qualifies.

Together, the four of them form a family of sorts: the science-minded father, a bit cold-blooded and emotionally oblivious; the artistic mother, who like her husband is something of a spoiled brat; the quasi-grandmother, enamored of horoscopes and vulnerable to portents of doom; and the child, whose connections with the others are this group's strongest ties.

Yet remove Mrs. A., and it becomes a different organism, far less sure of its validity and strength, much more suspicious of the games it's been playing.

"Like Family" is a snugly perfect fit, then, for this stock-taking time of year, when we notice at holiday gatherings the ways families expand and contract, how they can transform elementally with the addition of a new member or the loss of an established one. The balance of any tribe is more delicate than we like to think, and altering it can upset the order in unexpected ways.

"Of the three of us," the physicist notes, "Emanuele is the only one who has not yet learned that nothing lasts forever when it comes to human relationships. He is also the only one who doesn't know that this is not necessarily a disadvantage."

True. But try telling that to someone whose family is crumbling around him.

LIKE FAMILY

By Paolo Giordano

Translated from the Italian by Anne Milano Appel

Viking, 146 pp., $22