Robert F. Kennedy Jr. and his wife Mary arrive at funeral services for U.S. Sen. Edward Kennedy in August 2009.

Story highlights

NEW: Mary Kennedy, 52, died of asphyxiation due to hanging, a local official says

She is called a gifted architect and a "relentless advocate of green design"

She married Robert F. Kennedy Jr. in 1994, and the couple had four children together

He filed for divorce in 2010, the same year Mary Kennedy was arrested for DWI

New York CNN —  

Mary Kennedy, the estranged wife of Robert F. Kennedy Jr., had been in the headlines for her alcohol and drug problems, but is remembered by relatives as a devoted mother and pioneer of “green” architecture.

Mary Kennedy’s family blasts stories on her death

A dark-haired beauty, Mary Richardson met Robert F. Kennedy Jr. through her friendship with his sister Kerry Kennedy, a roommate from school.

The couple married in a civil ceremony in 1994 when the designer was six months pregnant, according to the Westchester County Journal News in New York. One month before the wedding, Kennedy divorced his first wife, Emily Black, the mother of his two oldest children, the newspaper said.

He and Mary Kennedy were together for 16 years before he filed for divorce two years ago, said her family attorney, Kerry A. Lawrence.

Mary Kennedy’s funeral set for Saturday

The pair, who had four children together, were still married at the time of her death Wednesday at home in Westchester County.

The 52-year-old died of asphyxiation due to hanging, said Donna Greene, a spokeswoman for the Westchester County medical examiner.

Both sides of the family paid tribute to Mary Kennedy as a devoted mother.

“It is with deep sadness that the family of Robert F. Kennedy, Jr. mourns the loss of Mary Richardson Kennedy, wife and mother of their four beloved children. Mary inspired our family with her kindness, her love, her gentle soul and generous spirit,” a statement by her husband’s family said.

Outside the home, Mary Kennedy made her mark as an architect who pushed the boundaries of eco-friendly design.

She was “a tremendously gifted architect and a pioneer and relentless advocate of green design who enhanced her cutting edge, energy efficient creations with exquisite taste and style,” her husband’s family said.

She also advocated finding a cure for food allergies and asthma and was a co-founder of the Food Allergy Initiative, the world’s largest private source of funding for food allergy research, Robert F. Kennedy Jr.’s family said.

Her own family paid tribute to “our beloved sister Mary, whose radiant and creative spirit will be sorely missed by those who loved her,” including the four children she loved “without reservation.”

Mary Kennedy’s death was the latest for a family that has seen its share of tragedy.

“We know from a history of this family, it’s very hard being a Kennedy, either being a blood Kennedy or being married to one,” Laurence Leamer, a Kennedy biographer, said on CNN’s “Erin Burnett OutFront.”

“The overwhelming celebrity, the attention, the obligations, the expectations that you’re supposed to do something with your life. It’s very, very hard.”

In 1968, Robert F. Kennedy Sr. was assassinated in California while making a run for the White House. His death came less than five years after his brother, President John F. Kennedy, also died at the hands of an assassin.

More than three decades later, in 1999, John F. Kennedy Jr.; his wife, Carolyn Bessette Kennedy; and his sister-in-law, Lauren Bessette, died when a plane he was piloting crashed in the waters off Martha’s Vineyard, Massachusetts.

David Kennedy died of a drug overdose in 1984, and Michael Kennedy was killed in a skiing accident in 1997. Both were sons of Robert F. Kennedy Sr.

Robert F. Kennedy Jr., a prominent environmental lawyer who is a professor at Pace Law School in White Plains, New York, is the third of 11 children born to Ethel and Sen. Robert F. Kennedy.

Details of the couple’s private life were exposed after Robert F. Kennedy Jr. filed for divorce from Mary Kennedy in Westchester County on May 12, 2010.

The next evening, according to police records, police in Bedford, New York, responded to a 911 call. When police arrived at the Kennedy residence, they found the couple in an argument over taking their four children to a carnival at St. Patrick’s School.

According to a “domestic incident” report filed by the officer on the scene, “Mr. Kennedy stated that his wife was intoxicated and was acting irrational so he took the children to the carnival to remove them from the situation.”

No one was injured, the report said.

Two days later, Mary Kennedy was arrested for driving while intoxicated.

At the time, Bedford Police Lt. Jeff Dickans told CNN that a Bedford police officer saw Kennedy’s 2004 Volvo swerving onto the curb of Greenwich Road in Bedford and asked her to pull over.

Kennedy had slurred speech and a blood-alcohol content above 0.08%, the legal limit in New York. She was charged with driving while intoxicated.

Lawrence, her family attorney, said the case resulted in a reduction to a violation, the criminal charge was dismissed, and her driver’s license was suspended for 90 days.

A second arrest occurred in August of the same year in the town of Pleasant Valley, in which she was charged with driving while impaired by prescription drugs, Lawrence said. Those charges were dismissed completely in July 2011 because all the drugs were prescribed and taken as her physician advised, the attorney said.

As a designer, Mary Kennedy sought to advance environmental principles and green technologies.

In a book titled “Kennedy Green House” that was co-authored by Robert F. Kennedy Jr., he describes how he and his wife restored their flooded, black-mold-infested home, transforming it into an eco-friendly residence.

A website devoted to the project describes how it focused “on maximum energy and water efficiency and improved indoor air quality to benefit the future of our planet and health of our children.”

In the book, her husband wrote that she had worked for the design firm Parish-Hadley and worked on the renovation of the Naval Observatory in Washington, the official residence of the U.S. vice president.

CNN’s Nina Ibarra contributed to this report.