US President Joe Biden broke down in tears at Knock Shrine earlier, after a chance meeting with the priest who performed the last rites on his late son.
46-year-old Beau Biden died in 2015 from brain cancer, and received his final prayers from Fr Frank O'Grady.
President Biden was unaware that Fr O'Grady was now based in Knock.
US President Joe Biden visiting Knock Shrine and Basilica in Co Mayo with Fr Richard Gibbons. Picture by: PA Images / Alamy Stock PhotoFr Richard Gibbons, who showed President Biden around the shrine, said it was "quite an emotional day."
"He arrived at the basilica and I greeted him inside - then he started speaking about how much it meant to his family.
"Then he started speaking about his son Beau who died, and he was getting a little emotional about that.
"It just so happened that we had a priest here who prayed with Beau before he died".
Fr Gibbons said Fr O'Grady was attached to the chaplaincy of the US Army.
"Then he wanted to meet Fr Frank... we didn't know anything about that story until hours before that," he said.
Fr Richard Gibbons, parish priest of Knock Shrine in Co Mayo, in August 2018. Picture by: PA Images / Alamy Stock PhotFr Gibbons said President Biden then met Fr O'Grady, before having some time alone.
"We went to the altar, he lit a candle for his own intentions and those of his family," he said.
"We came down to a seat and we knelt, and prayed a decade of the rosary together.
"Then I left him be; I said, 'Mr President, I'm going to leave you for a few moments of self-reflection' - and he said, 'Yeah I'd like that'.
"He was quite emotional at that point too. You can see it meant an awful lot to him.
"It was just the full range of emotions, really.
"We talked, we spoke, told stories, he laughed and then he cried.
"It was just the full spectrum, and it meant an awful lot to him."
US President Joe Biden addresses the Joint Houses of the Oireachtas. Picture by: Oireachtas screenshotFr Gibbons said President Biden just wanted to tell his story.
"I meet an awful lot of people here," he said.
"They want to tell you their story, and that's what he did - he wanted just to tell me his story and his family.
"It was done in a faith-based manner and just connect in that way.
"And we do what we do [which is] is we listen - you just listen to the stories that are given and then you pray with the individuals concerned.
"It felt very much like that, like a pilgrimage," he added.
President Biden was given a stone from the wall of the apparition to commemorate his trip.
Additional reporting: Mairéad Cleary
