Francis recalled how one grandfather had told him to "never go to bed without saying something to Jesus; tell him goodnight." This reinforcement combined with the prayers he learned from his grandmothers and his mother helped reinforce the faith, he said.
"Grandparents have the wisdom of life, and with that wisdom they teach us to grow closer to Jesus," he said, urging the youth to talk to their grandparents, "ask them whatever questions you want. Listen to what they say."
Playing with friends also helps, he said, because in knowing how to play well with others, "without insulting each other," you learn "to respect others, you learn to make a team, to work together, and this unites us to Jesus. So play with your friends!"
Parish life is also crucial, he said, and jestingly encouraged the youth to have the same excitement about Mass as they do about their groups and activities.
When answering the couple's question on how they can transmit the beauty of the faith to their children without sounding boring, annoying or authoritarian, Pope Francis advised them to think of who helped them to grow in the faith.
He asked the stadium to take a moment and ponder the answer in silence, explaining that an important figure for him was the priest who baptized him and who was then present throughout his life until he entered the novitiate with the Jesuits.
"I never, never forget that priest. He was an apostle of the confessional; merciful, good, a hard worker. And so he helped me to grow," the Pope said, explaining that he asked for this reflection because "our children watch us constantly; even when we are not aware."
On this point, as he often has in the past, Francis warned against the damage it can do to children when they see their parents fight.
"You don't understand the suffering a child experiences when they see their parents fight, they suffer. And when their parents separate, they pay the price," he said, explaining that when parents bring a child into the world, "you must be aware of this."
"We take responsibility to help this child grow in the faith," he said, and suggested that the couple reach Chapters 1 and 4 of his post-synodal apostolic exhortation Amoris Laetitia, a fruit of the 2014 and 2015 Synod of Bishops on the Family.
Dedicated to love in marriage and in the family, the Pope told them the chapters, particularly the first, would be helpful, and told them to never forget that "when you fight, children suffer and they don't grow in the faith."
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He also stressed the importance of playing with their children and practicing the works of mercy together, which help nourish faith and family life.
Sunday's are an especially good day to spend together as a family, he said, but noted that for some this is hard to do, since many have to work on weekends in order to provide for their families.
"Parents at this time can't or have lost the virtue of playing with their children," he said, explaining that whenever when he hears a parent complaining about their children's behavior, he often asks if they take time to just sit and play with their children.
Many parents "don't know how to respond," he said, recalling how he once spoke with a father who only saw his children on the weekends, since he left for work while they were still asleep and came back after they were already in bed.
"It's this life that takes your humanity," he said, and told parents to "play with your children, and transmit the faith."
Elise Harris was senior Rome correspondent for CNA from 2012 to 2018.