It’s hard to believe we don’t know all there is to know about the Kennedys. Yet we once again are in a moment when pop culture taps into America’s endless fascination with the political dynasty.

There’s a CNN series now airing about the famous family and a new feature film, “Chappaquiddick,” that chronicles events surrounding the car accident that led to the death of a young woman named Mary Jo Kopechne and derailed Ted Kennedy’s presidential ambitions.

Still, those projects tend to focus on the men. Which is why “Eunice: The Kennedy Who Changed the World” (Simon & Schuster, $28) is a revelation.

Many likely recognize Eunice Kennedy Shriver — who married activist and diplomat Sargent Shriver in 1953 — as the founder of and force behind the Special Olympics. In this new biography, author and Pulitzer Prize-winning columnist Eileen McNamara reveals with meticulous detail and matter-of-fact prose Shriver’s relentless drive, nervous energy and lifelong efforts to affirm the dignity and abilities of those with special needs.

McNamara relies on letters, family records and the observations of acquaintances and family to sketch a nuanced portrait of a woman who was brusque yet charismatic, demanding and, at times, imperious but also down-to-earth.

We learn that Shriver, the middle child among the Kennedy siblings, was perhaps the most like John F. Kennedy, the brother she adored. They shared a Georgetown home early in Kennedy’s political career, struggled with the same frail health and even sounded alike when they spoke.

Shriver pushed her brother to create the National Institute of Child Health and Human Development, which would go on to initiate life-saving research in the realms of maternal and child health. Shriver also was an informal adviser to the president, frequently popping by the White House to share her opinions and priorities.

“Eunice” doesn’t make a clear declaration that Shriver’s activism was solely driven by concern and guilt about Rosemary Kennedy, the sister who was developmentally delayed and then permanently crippled after her father made the decision to have her undergo a prefrontal lobotomy in November 1941.

But we learn that Eunice Kennedy was the one who would play with Rosemary and take her sailing as a child. And she would honor her sister’s life by ensuring that others with similar capabilities were nurtured, respected and included.

In this April 28, 1961, photo, President John F. Kennedy stands during a welcoming ceremony at O'Hare Airport as Mayor Richard J. Daley looks on, with Kennedy's sister Eunice Kennedy Shriver, at left, and some of her children.

In this April 28, 1961, photo, President John F. Kennedy stands during a welcoming ceremony at O’Hare Airport as Mayor Richard J. Daley looks on, with Kennedy’s sister Eunice Kennedy Shriver, at left, and some of her children. | AP

“Eunice” also highlights Shriver’s other passions. For instance, while fighting for better treatment of those with special needs was her primary focus, Shriver was no less a champion for women and youths who had been incarcerated, advocating that they be seen, mentored and given second chances.

She also raised five children, including journalist and former California first lady Maria Shriver. She died on Aug. 11, 2009, at 88.

“Eunice” offers glimpses of iconic events, such as how Shriver knelt dry-eyed to pray when she learned that JFK was assassinated. But those much-chronicled points in history aren’t dwelt upon.

Because this is Eunice’s story. It’s about time.

Author Eileen McNamara.

Author Eileen McNamara.