Political First Lady Rosalynn Carter met with dictators and promoted mental health care - but it was her 77-year marriage to Jimmy that is among her top achievements

Former First Lady Rosalynn Carter passed away at the age of 96 on Sunday, and is being remembered not only for her life as a devoted wife and mom, but for her political activism. 

The first lady with the longest marriage on record - 77 years - was sometimes referred to by her husband's aides as 'co-president,' because of her holistic involvement in President Jimmy Carter's decision making as he led the nation.

Rosalynn Carter is said to have defined the modern role of the First Lady. She viewed herself not just as a figurehead and accessory to her husband, but as an activist with significant influence.

She became known as 'the Steel Magnolia,' a reference to her soft-spoken Southern demeanor and accent, underweather which lay an iron-will and ambition to rival her husband's.

When Jimmy Carter lost in a landslide to Ronald Reagan in 1980, it was Rosalynn Carter, not the former president, who contemplated a potential political comeback.

In the years following their life together in DC, both halves of the couple said it was she who had been the more political of the pair.

In 1977, just months into his term, President Carter sent Rosalynn on a political mission to Latin America to convey the message to dictators that his administration was serious about denying aid to those who violated the human rights of their people.

At various points during Carter's single term, Mrs. Carter was forced to publicly deny that she was carrying undue influence over the goings-on of the US government.

For all of her excitement about politics and being invovled in her husband's career, she said that once the president had made up his mind, she had not real ability to change it.

In an anecdote shared by the New York Times, the president, in early 1977, decided to lower the White House thermostats to 65 degrees by day, and 55 degrees by night - a strategy to conserve energy.

When her husband denied her plea to turn up the heat, she opted to exclusively wear long underwear until such a time that he may reconsider. 

As a servant of the people, Carter chose mental health and issues plaguing the elderly as her central cause for political emphasis. 

She served as the honorary chairwoman of the President's Commission on Mental Health. 

In her capacity as chairwoman she once testified before a Senate subcommittee, becomin the first first first lady to address a congressional panel since Eleanor Roosevelt.

Some 16 years ago, Rosalynn was back in DC before Congress, continuing to push for mental health coverage.

'We've been working on this for so long, it finally seems to be in reach,' she said in 2007.

She credited her time spent on her husband's campaigns for the Georgia governorship with her interest in mental health.

'I used to come home and say to Jimmy, "Why are people telling me their problems?" and he said, "Because you may be the only person they'll ever see who may be close to someone who can help them."' she said.

Famously, the Carters built a large American family. The pair produced four children of their own - three boys and a girl, and in turn, became grandparents to 22 grandchildren and great-grandchildren. 

Eleanor Rosalynn Smith was born in Plains on Aug. 18, 1927, the eldest of four children. Her father died when she was young, so she took on much of the responsibility of caring for her siblings when her mother went to work part time. 

She also contributed to the family income by working after school in a beauty parlor. 'We were very poor and worked hard,' she once said, but she kept up her studies, graduating from high school as class valedictorian.

She soon fell in love with the brother of one of her best friends. Jimmy and Rosalynn had known each other all their lives - it was Jimmy’s mother, nurse Lillian Carter, who delivered baby Rosalynn - but he left for the Naval Academy in Annapolis, Maryland, when she was still in high school.

In a statement released by the Carter Center, President Carter called Rosalynn his 'equal partner in everything I ever accomplished.'

'She gave me wise guidance and encouragement when I needed it. As long as Rosalynn was in the world, I always knew somebody loved and supported me,' he said.

She is survived her her children, Jack, Chip, Jeff, and Amy, in addition to 11 grandchildren and 14 great-grandchildren.

Her son Chip said of his mother: 'Her life of service and compassion was an example for all Americans. She will be sorely missed not only by our family but by the many people who have better mental health care and access to resources for caregiving today' 

Her passing follows the decision in February of this year to transition the former president into end of life care following 'a series of short hospital stays.'

She died on November 19, at her Plains, Georgia home, surrounded by family.