VATICAN CITY — Pope Francis welcomed the president of Argentina’s famed “Mothers of the Plaza de Mayo” to the Vatican on Wednesday, putting him face-to-face with one of his country’s best-known human rights activists and a one-time critic of the pope.

Carlotto, who not so long ago voiced doubts about then-Cardinal Jorge Mario Bergoglio’s record under Argentina’s military junta in the 1970s, described her 30-minute with Francis as “marvelous.”

“We spoke very freely, very frankly,” she said. “It was very beautiful.”

By the end, any doubts harbored by the 84-year-old activist over the future pope’s role were seemingly left behind.

To be sure, Carlotto’s investment in the legacy of Argentina’s “Dirty War” is deeply personal, given that she was recently reunited with her grandson after a 36-year search.

Carlotto’s daughter Laura was pregnant when she was abducted, tortured, and killed during the Argentinian 1976-1984 military dictatorship. Her grandson, Ignacio, was born during this time and as with hundreds of other children born in the clandestine detention centers, he was given away to a foster family with ties to the military.

“Grandmothers” is a branch of the Mothers of Plaza de Mayo, an association set up to track down those who disappeared during Argentina’s last military dictatorship. In most cases, the mothers don’t know what happened to their children, while the grandmothers, certain of their deaths, focus on searching for their offspring.

Since the group’s inception, during the military junta, and thanks to a DNA bank set up by families and survivors of the dictatorship, 115 people have discovered their true identities.

Shortly after Carlotto’s grandson’s recovery last August, Pope Francis sent a letter to the activist expressing his respect and admiration for the work done by the Grandmothers of the Plaza de Mayo.

“Thank you, madam, for your endless and tireless struggle,” the pope wrote. “It brought happiness to my heart after I heard that you found your grandson and I ask the Lord that your hard work and tenacity are rewarded in spades.”

The pontiff received gifts from the family, including a CD of music composed by Ignacio, and a white scarf that’s become the symbol of the Grandmothers association.

When the announcement of his election was made back in March 2013, Argentina’s Dirty War was one of the clouds looming over Pope Francis. The Mothers of Plaza de Mayo were among the most vocal opponents, saying that the then-Jorge Mario Bergoglio had been an accomplice in the disappearance of two of his fellow Jesuits while he was the local head of the order.

The charges were refuted by Argentinian Nobel Peace Prize Winner Adolfo Pérez Esquivel, and later by the book “Bergoglio’s List: The Untold Story of the People Saved by Francis during the Dictatorship,” whose author, Italian journalist Nello Scavo, asserted that Francis was actually a Jesuit version of Oskar Schindler, quietly saving lives.

On March 15, 2013, Carlotto gave a radio interview in which she gave the newly elected pontiff a “vote of confidence in this new mission,” but warned that he should make a “mea culpa” if he committed “a crime or a mistake” during Argentina’s military dictatorship.

“There is always time,” she said to reporters of Millennium radio station.

“When someone commits a crime or a mistake, even if it is not considered a crime, there is time to think over and make a mea culpa. I think it is a supreme Christian act to confess a sin, to repent and feel contrition,” she said.

At the time, Carlotto commended Bergoglio for helping with various excruciating issues, such as poverty and human trafficking, but questioned him for not helping with the search of the desaparecidos.

“Bergoglio belongs to the Church that darkened the history of the country,” she had said.

Yet on Thursday, during a press conference held in the Argentinian Embassy to Italy, Carlotto regretted her declarations, admitting that she had made a mistake when criticizing the pontiff.

“Anyone who still accuses Bergoglio of being an accomplice of the military dictatorship is lying because the truth is already known,” she said.

The activist also announced that Pope Francis has authorized opening the Vatican’s archives on the Argentinian dictatorship to help find still-missing children. She also said the pontiff told her he plans to travel to his native Argentina in 2016.

Carlotto said she asked the pope during their audience when he was coming to Argentina, and he replied in 2016.

The Argentine-born pontiff was unable to add his homeland to his schedule when he traveled to Brazil last year for World Youth Day.

The Vatican does not, as a rule, confirm papal travel plans until several months ahead of time.

Material from the Associated Press was used in this report.