ROME – Joseph Ratzinger, better known as Pope emeritus Benedict XVI, now at the ripe age of 93, is scheduled to return to Rome this morning after a quick trip to Regensburg to visit his ailing 96-year-old brother – a trip which, given his increasing frailty and desire to keep a low profile, has been described by many observers as his last ‘cameo’.

Benedict’s older brother, Georg Ratzinger, reportedly is seriously ill and, perhaps, near death. The Ratzinger brothers are known to be close, so it would be hard to imagine Benedict would miss the opportunity to say goodbye.

While it was a demanding trip, as it would be for anyone in their 90s, especially in the middle of a global pandemic that targets the elderly, the brothers seem to have made the most of it, spending much of their time in prayer and conjuring up old memories.

Benedict landed in Munich around 11:45a.m. Thursday and was welcomed by the Bishop of Regensburg, Rudolf Voderholzer. He stayed at the diocesan seminary throughout his visit, and was accompanied by his personal secretary, German Archbishop Georg Gänswein, his doctor, a nurse, and one of the religious women who run his Vatican residence.

Shortly before departing, Benedict had a brief visit with Pope Francis, who gave him the greenlight to make the trip and bid him farewell.

After his arrival, Benedict visited his brother and the two celebrated Mass together at Georg’s residence. Benedict, tired from his travels, then went back to the seminary to rest during the afternoon but ventured out to see his brother again that evening.

On Friday morning, Benedict was served a traditional Bavarian breakfast at the seminary, complete with pretzels, which the diocese said Ganswein was particularly pleased by.

The Ratzinger brothers then celebrated Mass together for the feast of the Sacred Heart of Jesus, and afterward shared apple strudel. That evening, Benedict visited his brother again for about an hour before returning to the seminary.

On Saturday, the brothers shared what the Diocese of Regensburg described as “a constructive and moving” encounter, with Benedict being “exhausted, but full of joy.”

They began by celebrating Mass together, and were later joined by Croatian Archbishop Nikola Eterović, the papal ambassador to Germany.

That afternoon, Benedict visited his former home in Pentling, which was his private residence from 1970-1977 while he was still a professor of theology at the University of Regensburg. The last time Benedict visited the house was during his 2006 trip to Germany while he was still pope.

He stayed there for roughly 45 minutes and was able to spend some time in the garden – a favorite place for Benedict even during his time at the Vatican, where even after his retirement he would go every afternoon to pray the rosary.

Later that day, Benedict visited the graves of his parents and his older sister, Maria, who died in 1991, in the Ziegetsdorf cemetery, where he prayed an Our Father and a Hail Mary before returning to the seminary.

Dr. Christian Schaller, Deputy Head of the Institute Pope Benedict XVI, said Benedict’s visit to his old home was a time when “memories awoke,” according to the Regensburg diocese, describing it as, “a trip back in time.”

“I have the impression that the visit is a source of strength for both brothers,” Schaller said.

On Sunday morning Benedict celebrated Mass with his brother again, and they did so a second time later that afternoon.

That evening, Benedict visited the city’s Cathedral of St. Peter, where relics of St. Wolfgang of Regensburg had been placed on display.

At Mass earlier that morning, Eterović, who stayed in Regensburg the whole weekend, told those watching the cathedral’s livestreamed Mass that it was “an honor to greet the retired Pope in Germany again, even in this difficult family situation.”

Eterović said that throughout his time with Benedict, he had the impression that the retired pontiff “feels good here in Regensburg,” and he thanked Catholics in the diocese for the respect and friendship they showed to Benedict, “so that the retired pope feels at home in this city and here in Bavaria.”

Benedict is scheduled to take off from Munich and land in Rome sometime the Vatican Monday morning.

Before the return date of his trip was announced, speculation exploded as to whether Benedict would ever return to the Vatican, with some saying he was too disgusted by Vatican corruption, others saying he would not be able to support the direction of the Church under Pope Francis, and still others saying he would stay in Germany to serve as a counterweight to the progressive line taken by many of the country’s bishops.

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Regensburg’s announcement of Benedict’s return Monday laid those speculations to rest.

Though many assumed Benedict would at least stay through his brother’s death and funeral, his return Monday means that much like the Diocese of Regensburg said at the beginning of Benedict’s visit, this was likely “the last time that the two brothers, Georg and Joseph Ratzinger, see each other in this world.”

It also implies that Benedict is unlikely to travel again, even when his brother passes and is laid to rest, meaning this could very well have been Benedict’s last public appearance.

When Benedict retired in 2013, he famously said that he would be “hidden from the world,” however, he has made several appearances since then at Pope Francis’s invitation, and he continued to receive visitors, write essays and make contributions to books, some of which have caused controversy and been used to pit Benedict and his successor against one another.

In February 2014, Benedict XVI made his first public appearance since his retirement, joining Pope Francis in a consistory to install 19 new cardinals named by his successor. It was the first time the two had been seen at a public liturgical ceremony together since Benedict’s retirement in 2014.

Benedict also attended the inauguration of the Jubilee of Mercy in 2015. He was present inside St. Peter’s Basilica when Pope Francis opened the holy door, officially opening the extraordinary year. Benedict himself then passed through the door and greeted Francis at the entrance to the basilica.

In 2015, he traveled to the papal residence in the Italian town of Castel Gandolfo to receive an honorary doctorate in sacred music from the Pontifical John Paul II University in Krakow. In 2016, he gave a brief speech to members of the College of Cardinals marking the 65th anniversary of his ordination to the priesthood.

On that occasion, he recalled how on the day of their ordination (the Ratzinger brothers were ordained together in 1951), a fellow priest ordained with them chose one Greek word to put on his ordination card, Efkaristomen, meaning “let us give thanks.”

“Efkaristomen sends us again to that reality of thanksgiving, to that new dimension that Christ has given,” Benedict said at the time, explaining that Jesus has transformed into thanksgiving “the cross, suffering and all of the evil in the world.” In doing so, he said, Jesus “fundamentally transubstantiated” life and the world.

After Benedict’s appearance at the consistory in 2014, Pope Francis said that, “it gives me great pleasure that he lives here in the Vatican, because it is like having a wise grandfather at home.”

Benedict has also had a public profile through his writings, most recently a lengthy 2019 essay on what he believes are the roots of the clerical sexual abuse crisis – published shortly after Francis held a major global summit on child protection – as well as a contribution he made in February to a book defending priestly celibacy written by Guinean Cardinal Robert Sarah, and which was published at a time when many observers believed Francis might be considering relaxing it.

In both cases, Benedict’s writings caused controversy, with some attempting to pit his reflections against the approach taken by his successor, Pope Francis.

Despite the controversies, Francis has consistently praised Benedict and continues to send him greetings for major feast days and on his birthday and has visited him multiple times. It is likely Pope Francis will welcome Benedict back after his return to the Vatican on Monday morning.

Follow Elise Ann Allen on Twitter: @eliseannallen