Steve Luxenberg’s book, “Annie’s Ghosts,” is part journalism, part social history and part family memoir.

Steve Luxenberg is a journalist and a son, and he is scrupulous about fulfilling his differing responsibilities down to the smallest detail. But sometimes, the two roles he’s played haven’t always jibed.

On at least one notable occasion, the son prevailed. At other times, the reporter won out.

Luxenberg’s book, “Annie’s Ghosts,” which was published last month, is part journalism, part social history and part family memoir. It also can be read as the author’s struggle to reconcile the competing parts of himself: paying his familial duty to his mother while remaining true to the values of his profession.

“I think I did succeed in being both a journalist and a son,” says Luxenberg, an associate editor for The Washington Post, and a former reporter and editor for The Baltimore Sun.

“At least, I hope I did. I didn’t hold back on the readers. I didn’t leave out facts of any importance, but I also remained empathetic to my mother. One bookseller told me, ‘There’s a lot of love in your book.'”

That author’s internal conflict began in 1995, when he learned that his mother was not the only child that she claimed to be for nearly all of her life. In reality, Beth Luxenberg had a disabled younger sister named Annie, who, decades earlier, had been sent away to an institution in Michigan. Beth had hidden Annie’s existence from everyone: her neighbors, her closest friends, her three sons and two stepdaughters, and possibly her husband.

After Beth died in 1999, her journalist son set out to find out as much as he could about the aunt he never knew. He also wanted to figure out why his mother, who taught her children to always tell the truth, had lied about a matter of such importance.

Deliberate error

Critics have commented on the hybrid nature of “Annie’s Ghosts,” which mixes objective and subjective methods of storytelling. It’s a rare memoir in that it contains 22 pages of footnotes.

The author’s obvious passion for the truth is one of the most touching aspects of the manuscript. Luxenberg, 56, bends over backward to avoid inadvertently coaching his sources and tainting their recollections. He is painstaking about distinguishing between what he knows for a fact and when he is unavoidably drawn into making suppositions.

That compact with his readers is why Luxenberg eschewed the narrative storytelling style now in vogue, which uses fictional techniques to tell real-life stories. His prose style is plain and unadorned, without fanciful images or hyperbole.

“One of the things this book is about is the distortions that memory imposes on truth,” he says.

“In some instances, I’m interviewing people about events that happened 50 years ago. I couldn’t bring myself to pull a fast one on the reader by telling them that this is the way things really happened.

“I also saw it as an opportunity to teach readers about the methodology that journalists use. My experience is that people enjoy being shown how the sausage is made.”

Yet for all Luxenberg’s diligence, there was one time when he deliberately allowed an error to make it into print. When Beth Luxenberg died, Steve prepared information for the obituary that ran Sept. 3, 1999, in the Free Press. The article describes her as “an only child of immigrant parents” — a statement the author knew to be false.

“That is the most mystifying thing to me,” Steve Luxenberg says.

“I had known about my aunt for several years. So how could I, as a journalist, write that my mother was an only child? Maybe I was being respectful of the way she’d want to be remembered. Or maybe I didn’t fully believe that she really had a sister.”

Roundabout truth

Annie’s existence came to light in 1995 in a roundabout manner, in a phone call made by a social worker to Luxenberg’s half sister, Marsha Rosenberg. She told Steve about Annie, and they later told their siblings.

But though Beth Luxenberg lived for four more years, none of her children ever asked their mother about their aunt.

Steve’s elder brother, Michael, who lives in Seattle, explains that the siblings grew up with assumptions that would have made it difficult for any of Beth Luxenberg’s children to confront their mother about her secret.

“In our family,” he says, “we were taught to stand on our own two feet. I must have heard that a million times. And we were taught to always look forward and to never look back.”

Beth Luxenberg’s death might have made it more difficult from a practical standpoint for her second son to find out the details of Annie’s life. But perhaps it made the author’s pursuit of the truth easier.

“My experience is that she would not have revealed the truth in the first conversation, or the second conversation, or the third conversation, or maybe not ever,” Steve Luxenberg says.

“She would have modified what she told us to conform to what we know at the time. I certainly wouldn’t have been willing to torment my sick mother about a secret that wasn’t mine, in order to tell a story that wasn’t my story to tell.”

In one sense, of course, Beth’s secret was Steve’s secret because it affected the son’s understanding of, and relationship with, his mother. So Michael Luxenberg was ambivalent when, several years after Beth’s death, Steve told his siblings he wanted to research and write “Annie’s Ghosts.”

“I didn’t think my mother would like the idea for this book,” Michael Luxenberg says. “But after discussing the book with Steven, I realized it was very important to him, and I told him I’d support him 100 percent.

“Besides, ‘Annie’s Ghosts’ doesn’t pretend to be a full and complete picture of my mother. Steven uses my aunt’s story to talk about larger issues: immigration, and the Holocaust, and mental institutions.”

Childhood understanding

The brothers’ half sister, Marsha Rosenberg, says reading “Annie’s Ghosts” provided insights into the woman who helped raise her.

“Steven’s book helped me understand more about my childhood, about what was going on in Beth’s life at the time,” she says.

“I don’t know how she would feel about the book, since she chose not to tell us her secret. I would hope she would not be upset, particularly since the only thing that reading Steven’s book did was make me more empathetic toward her. She had really difficult things to deal with.”

In the final pages of “Annie’s Ghosts,” Steve Luxenberg echoes his sister’s thoughts. “I’m here,” he imagines telling Beth. “I’ll always be here, I’m not leaving. I love you, and no, nothing you say, nothing you tell me will make me go away.”

The journalist had to tell the truth, but the son’s love for his mother never wavered.