Robert Kolker begins THE VANISHING FAMILY with a perfectly normal family tree. Oliver and Jean meet on a train to Notre Dame in the late 1940s, and they marry in 1950. Kathy, Christy, Sue, Dutch and Mary are born in the first 10 years, followed by Peggy, Scott and Jenny. Ten years later, Barb is born. As in all families, birth order matters. How the children align themselves with certain siblings and how they respect one another’s choices from close up or from afar matters as well.

THE VANISHING FAMILY is narrative nonfiction. This family is authentic, although no last names are used and several of the children choose pseudonyms as their collective frontotemporal dementia (FTD) manifestations and behaviors are revealed and catalogued by Kolker. The heading of each chapter lists the siblings in birth order, highlighting the family member under discussion.

The prologue takes place in Denver in December 2017. Barb is home alone. A letter arrives from the Mayo Clinic in Rochester, Minnesota. She has been receiving letters, all unopened and discarded, for some time. She knows what each says. The Mayo Clinic wants to see her and give her the results of testing that she and her siblings undertook a while ago. Barb has declined to hear those findings, even though she feels that she must learn her fate. In fact, she has prepared two scenarios in her mind. In one, she and Dave (her husband of 10 years) will go home, prepared to live each moment to the fullest, peacefully and gratefully. In the other, she goes back to the motel, gets drunk, quits her job, gets a tattoo and disappears.

"It...is an enormous undertaking to keep track of the siblings and their marriages and families, to record distinguishing patterns of behavior, to make sense of employment and education, to document moves, houses and apartments over a great deal of the United States. But Kolker pulls this off brilliantly."

Neither strategy is used. Barb’s diagnosis will come later. 

However, Barb does become one of the primary characters in the discovery and analysis of the family’s connection to FTD. She loves her older sisters and knows them as strong, independent, creative women. She admires Sue’s adaptability and compassion, eventually becoming a caregiver for Christy, the first in the family to have FTD. She sees in Mary a strong-willed organizer and doer, while Peggy is a walking encyclopedia. And Jenny has been her role model forever, choosing prom gowns and makeup, curling her hair and teaching feminine hygiene.

In retrospect, it becomes apparent that Jean was showing the symptoms of FTD early in her 40s: depression, dependence on Manhattans, slovenliness about her appearance. She was loyal to her husband, although he was rarely home. The children were generally uncritical, but they quickly moved out of the home and into their own lives. The realizations about the devastating changes to their mother, years later, should have given Barb and her siblings some guideposts about what to notice and what to expect. 

However, even as some of them exhibit peculiar life changes themselves, they are unable to agree that what happened to their mother may be happening to themselves now. It is difficult to recognize and report inappropriate behaviors, especially for close relatives. These details change from person to person, but some are recognizable: lack of attention and affection to family members; an inability to make sense of ordinary conversation; ignoring sanitary norms of showering and using a toilet; withdrawal from social situations; inappropriate interactions with strangers; and wandering off. Without knowing and identifying some of these tell-tale markers, researchers cannot draw valid conclusions.

Kolker tracks the relevant events in the lives of this family, and at the book’s midway point he adds a long-unknown relative of Jean’s from Wisconsin. The discovery of another family member with FTD was accidental. It feels like many of the breakthroughs in diagnosing FTD happen through casual, seemingly unrelated events. This connection was made through a newspaper photograph of a grandfather who appeared in other family pictures. 

In other sections, Kolker details the timeline of documenting dementia in America, including the decisions that were made labeling essentially all dementia cases under Alzheimer’s. While these steps increased much-needed funding and public recognition, they may have stymied research for specific strands, such as FTD.

As Barb watched the disease consume Christy, and then more people she loved, she remembered the Mayo Clinic and the voice of the well-respected and understanding Dr. Boeve: “The science is very easy.” What? 

Barb searched the internet late at night and saw that just as there are many different types of dementia, so, too, are there various subcategories of FTD. Not all inherited FTD is alike. The three most common varieties are created by the overproduction of three different proteins. Barb’s family has a tau mutation. The other two mutations have the unwieldy names progranulin and C9orf72. 

How is this easy? 

FTD has one crucial quality that many of the more common conditions like Alzheimer’s does not. Even now, after more than a hundred years, researchers cannot look at a person’s DNA sample and say with certainty that they will get that disease. Barb’s family, meanwhile, can look at their genetic profile and quite literally see the mutation that will cause FTD. If the mutation is there, they have it. If it is missing, they will not.

So it is genetically easy. Which is a sad distinction, because easy to see does not mean easy to cure.

It is a Herculean task to keep honest research methods underway as the changing pieces of this puzzle are living out their lives. It also is an enormous undertaking to keep track of the siblings and their marriages and families, to record distinguishing patterns of behavior, to make sense of employment and education, to document moves, houses and apartments over a great deal of the United States. But Kolker pulls this off brilliantly. He listens to stories over and over again, and in the book’s last pages he tells us that Jean’s descendants are now making the decision that Barb faced years ago. Whether or not to be tested. Whether or not to know. Barb’s husband has an outsider’s perspective: Those who have FTD are so unselfconscious that they seem to suffer less than the family members around them, who are forced to watch them change.

The Epilogue is set in Pleasant Hills, Pennsylvania, in 1997, where they were raised. Charlie, Kathy’s 26-year-old son, is running the video camera. The siblings are laughing and clearly loving the inside jokes and connections. A perfectly normal family. 

In 2026, Kolker pauses the video and updates the story. He annotates the long-ago moments with the FTD status of each child and their family members.