Haunted by tragedy, Robert F. Kennedy’s large brood has been responsible for a fair amount of turmoil and misbehavior. Yet behind the harsh headlines, the brothers and sisters have been united in love for their mother. On October 18, HBO will debut Ethel, Rory Kennedy’s documentary about RFK’s widow. Through interviews with her eight living siblings as well as her mother, Kennedy creates a portrait of a mischievous and determined woman with a life story full of surprises. Among them:

Ethel’s parents, Ann and George Skakel, were conservative Republicans. Asked what they thought of her campaigning for Democrats, she says, “I think they thought I was a little Communist.”

She was arrested in 1967 for stealing horses. Spotting three starving animals near the family’s home, Ethel simply took them. The owner sued her for “horse thievery,” which, says her daughter Courtney, “in Virginia at the time was a hanging offense.”

In the past 20 years, she has joined human rights delegations to such spots as Namibia, Albania, Poland and Kenya. Onscreen, Ethel’s children credit her, more than their ­father, for fostering a commitment to public service. “The truth is, he died when we were very, very young,” says Kerry, “so that really was from my mother.”

Originally published in the October 2012 issue of More