When Jennifer Senior visited the Bartholomew family in Missouri City, Texas, it was a relatively quiet afternoon. That’s something of an anomaly in a house with five children.

Senior was researching a book, an expansion of her provocative 2010 New York Magazine article, “All Joy and No Fun: Why Parents Hate Parenting.” And she was looking for stories — snapshots in words — of busy 21st-century parents in the chaotic throes of family life.

“There’s intense pressure on nuclear families,” says Senior, 44, on a recent afternoon at Houston’s Hotel ZaZa. “We don’t have a script for our lives now.”

Angelique Bartholomew remembers she was cooking when Senior visited — tacos for the kids and husband, Brian — and she remembers answering honestly when Senior asked about the hardest part of having so many kids.

“Making sure they all feel like they’re important,” Bartholomew told Senior. “Because I know which one of them doesn’t feel like they’re as important. … No matter how much you put into your kids, some will need more than others.”

It was a brutally honest moment, revealing a truth many parents don’t talk about. Just the sort of candor Senior was looking for. Bartholomew’s answer ended up in Senior’s book, “All Joy and No Fun: The Paradox of Modern Parenthood,” now No. 6 on the New York Times best-seller list.

Senior interviewed families in Minnesota, New York and the Houston suburbs. She chose Houston, she says, because it has one of the fastest-growing populations of children younger than 18 in the country, because it’s so culturally diverse and because it’s filled with overscheduled parents who run themselves ragged — Cub Scouts, soccer, tutors and so on — in order to improve their children’s lives.

“All Joy and No Fun” is not a how-to book on parenting. It isn’t thick with lists and tips, or cliché admonishments to parents, like: Take time for yourselves! Plan a date night!

Rather, it’s a bittersweet book about how it feels to be a parent right now, in America — from the hazy, no-sleep months of struggling with a newborn, up through to adolescence, when parents must relinquish the physical control they have over their children. Around her snapshots of real-life families, Senior wraps research and data that outline significant shifts in our understanding of childhood and parenthood over the past 50, 75, 100 years.

Senior hopes parents will feel the thrill of recognition when they read the book.

“This is going to sound totally cheesy, but I want readers to go, ‘Oh! It’s not just me!’?” she says. “I want wives to be reading it and elbowing husbands in their rib cages.”

Today, parents work more than they did 50 years ago and spend more time with their kids than they did 50 years ago, Senior notes. If you do the math, that means very little grown-up time away from kids and work.

But what about the joy of the book’s title? Because there is joy, Senior says. Children provide parents with structure, purpose and stronger bonds to the world; they enrich their parents’ lives in ways that surveys and data never reflect.

The joy of parenting comes from connection, Senior says.

Joy is the long, low rumble of family love underneath good, bad and busy days. And there’s a poignancy to this joy, because it carries with it its opposite: loss.

In the book, Senior quotes American psychiatrist George Vaillant: “Joy is grief inside out.”

Today, Bartholomew’s own five children range in ages from 5 to 16. When the busy mom thinks back just a few years, to when the youngest were still underfoot, she’s amazed she got through it.

“It was pure chaos,” she says. “I was firing on every possible cylinder, for sure. Now I’m like, how didn’t I blow a gasket?”

These days, though, all Bartholomew’s children have a keen appreciation for how their family works.

“The paradox of modern parenthood for me is, ‘Hey, I really get joy and fulfillment, but this isn’t always the place I want to be.’ My kids all have a clear understanding of that. It’s like, ‘You know what, dude? I’m doing my part. You do yours.’ “