Philadelphia (CNN) The Walker family from Argentina traveled 13,000 miles in a remodeled Volkswagen bus to be in Philadelphia for the papal visit . Never in their wildest dreams did they imagine they would actually meet the Pope. But on Sunday, their phone rang at 6 a.m. It was the Vatican calling.

Pope Francis had taken notice of his fellow citizens from Buenos Aires and their 194-day journey through 13 countries. He decided to take the time to meet with Catire Walker, 41, his wife, Noel Zemborain, 39, and their four children, ages 3 to 12.

Walker said chaos ensued after the Vatican called and told them to head to the Saint Charles Borromeo Seminary. The six of them scrambled to get ready as fast as they could. When they arrived, still incredulous, they were told to wait in a hall. Within five minutes, they were standing before Francis.

"Are you the family who traveled from Buenos Aires? You're crazy," the Pope said, laughing.

The Walkers finally made it to the U.S. border on August 30.

The Walkers finally made it to the U.S. border on August 30.

After an unexpected delay in Guatemala, the Walkers were forced to skip Belize and go directly to Mexico instead. In Oaxaca, they joined the Assumption of the Virgin celebrations.

After an unexpected delay in Guatemala, the Walkers were forced to skip Belize and go directly to Mexico instead. In Oaxaca, they joined the Assumption of the Virgin celebrations.

Dimas, 8, affixes the Nicaraguan flag on the back of the bus. The children have been taking turns with the flag stickers, but when they reach the United States, all four plan to put on the Stars and Stripes.

Dimas, 8, affixes the Nicaraguan flag on the back of the bus. The children have been taking turns with the flag stickers, but when they reach the United States, all four plan to put on the Stars and Stripes.

The Walkers have visited several historic spots in Latin America on their journey. In Panama, they visited Fort San Lorenzo, which UNESCO has declared a World Heritage Site.

The Walkers have visited several historic spots in Latin America on their journey. In Panama, they visited Fort San Lorenzo, which UNESCO has declared a World Heritage Site.

Another birthday! This time, the family surprised Catire with a special breakfast on the 24th floor of the apartment building where they stayed in Panama City, Panama.

Another birthday! This time, the family surprised Catire with a special breakfast on the 24th floor of the apartment building where they stayed in Panama City, Panama.

The 1980 VW bus stands out wherever the Walkers go, even against the most scenic landscapes such as the mountains of Colombia.

The 1980 VW bus stands out wherever the Walkers go, even against the most scenic landscapes such as the mountains of Colombia.

The family has been grateful to people who have taken them in. They stayed at a farm near Bogota owned by Carlos and Claudia Mazabel.

The family has been grateful to people who have taken them in. They stayed at a farm near Bogota owned by Carlos and Claudia Mazabel.

The Walkers have been visiting Catholic shrines and churches on their journey. In Bogota, Colombia, they toured a cathedral built in a tunnel of a salt mine, the only one of its kind.

The Walkers have been visiting Catholic shrines and churches on their journey. In Bogota, Colombia, they toured a cathedral built in a tunnel of a salt mine, the only one of its kind.

At the port in Cartagena, Colombia, the Walkers had to empty the bus so that authorities could conduct a drug search.

At the port in Cartagena, Colombia, the Walkers had to empty the bus so that authorities could conduct a drug search.

It was a fun-filled day for Cala, 12, in Mancora, when she got to swim with the turtles.

It was a fun-filled day for Cala, 12, in Mancora, when she got to swim with the turtles.

Catire makes dinner on the beach in Mancora, Peru. The family packed camping gear to make the long trip affordable.

Catire makes dinner on the beach in Mancora, Peru. The family packed camping gear to make the long trip affordable.

The kids had fun on the beach in Pimentel, Peru. They've made many new friends on their epic trip.

The kids had fun on the beach in Pimentel, Peru. They've made many new friends on their epic trip.

The Volkswagen bus was relatively cheap and certainly endearing, but it has had its problems. Catire has had to fix it several times. Here, Chilean friend Rafa helps with the engine in Copiapo after the devastating floods and mudslides.

The Volkswagen bus was relatively cheap and certainly endearing, but it has had its problems. Catire has had to fix it several times. Here, Chilean friend Rafa helps with the engine in Copiapo after the devastating floods and mudslides.

In Copiapo, Chile, the Walkers were taken in by Angela Boggioni, back left, in the middle of disaster. Torrential rains flooded villages and towns in the Atacama Desert.

In Copiapo, Chile, the Walkers were taken in by Angela Boggioni, back left, in the middle of disaster. Torrential rains flooded villages and towns in the Atacama Desert.

In Concon, Chile, the family met Monica Ahumado, who, despite tragedy in her life, opened up her home.

In Concon, Chile, the family met Monica Ahumado, who, despite tragedy in her life, opened up her home.

The family began their journey with Mass at the cathedral dedicated to Our Lady of Lujan, Argentina's patron saint.

The family began their journey with Mass at the cathedral dedicated to Our Lady of Lujan, Argentina's patron saint.

It was important for the Walkers to spend time as a family. They traveled 13,000 miles through 13 countries together.

It was important for the Walkers to spend time as a family. They traveled 13,000 miles through 13 countries together.

Catire Walker, Noël Zemborain and their four children hopped in their 1980 Volkswagen bus in March and set off from Buenos Aires on a journey to see Pope Francis in the United States. Here the family celebrates their arrival in Philadelphia. From left are Dimas, Cala, Noël, Carmin, Mia and Catire.

Catire Walker, Noël Zemborain and their four children hopped in their 1980 Volkswagen bus in March and set off from Buenos Aires on a journey to see Pope Francis in the United States. Here the family celebrates their arrival in Philadelphia. From left are Dimas, Cala, Noël, Carmin, Mia and Catire.

Never in their wildest dreams did the Walker family think their 13,000-mile journey would culminate in a meeting with the Pope. But that's what happened in Philadelphia after the Vatican called.

Never in their wildest dreams did the Walker family think their 13,000-mile journey would culminate in a meeting with the Pope. But that's what happened in Philadelphia after the Vatican called.

It was exactly the reaction the family had predicted back in July when I'd asked them what the Pope might think of their long journey. But back then, they had no idea the Pope was following their travels -- the family keeps a blog and has been posting on Facebook and Twitter.

Walker said the conversation felt as though they were meeting an old friend for coffee. It was casual, laid-back and comfortable. He said the Pope recognized their courage for the journey they made as a family.

They told the Pope there were thousands of families in America that loved him and were praying for him. The Pope responded that he had enormous responsibilities and that he needed their prayers, Walker said.

The Walkers' odyssey from Buenos Aires to Philadelphia.

Vatican spokesman the Rev. Federico Lombardi acknowledged the Walker family at a press conference Sunday.

"The Pope has met an interesting Argentinean family who came in a Kombi (the VW bus) with four children, from Argentina to Philadelphia," Lobardi said. "The Pope said to me explicitly to say this because for him it was a very interesting moment, and the experience of this family has touched him very much."

The Walkers' eldest daughter, Cala, 12, threw her arms around the Pope's waist and would not let go. She had a rosary with her and asked Francis to bless it. Then, before departing, the entire family engaged in a group hug with the Pope.

"Thanks for coming," he told them.

"Thank you for inspiring us to go out and make a bit of trouble," they said.

As the Pope was leaving, he turned around and said with a chortle: "You are some troublemakers!"

In March the Walker family packed all they would need into their 1980 Volkswagen and began driving north from Buenos Aires. They were not hippies, they insisted, but admitted they were a taking a risk with such an adventure. But for Walker and Zemborain, it was important to make this road trip. It afforded them the time they wanted to spend with one another and their children.

"We celebrate the family. Ours and all," they said upon their arrival in Philadelphia, where they have been attending the 2015 World Meeting of Families. Their VW bus, named Francisca after the Pope, bears a sticker with the event's logo.

The Walker family finally made it to Philadelphia.

Their journey, said Zemborain, had been enriched by the many people they encountered along the route who opened up their homes and their hearts. She thanked them in a Facebook post.

"We are so happy. Today you were all in the van with us!"

Everywhere the family visited, the curious stopped to ask -- and were left in awe of the family's love for one another and their faith in God.

Faith, for the Walkers, has never been about church and its rituals but about the everyday occurrences of life. In Francis, they finally saw a pope who understood ordinary people like them, a pope who talked about things no pope had discussed openly before.

Besides, they felt immensely proud that Francis was a fellow Argentine. They had followed Jorge Bergoglio closely when he was archbishop of Buenos Aires and had even seen him up close right after he was named pope.

They made the journey of their lives to see him again in Philadelphia. Sunday, the Pope returned their efforts by making time to meet with them personally. It was, they said, the best gift of all at the end of a long journey.