Pope Francis sought Sunday to encourage married couples, acknowledging that the pandemic has aggravated some family problems but urging couples to seek help and always remember three keywords in a marriage: “Please, thanks and sorry.”

Francis penned a letter to married couples that was released Sunday, a Catholic feast day commemorating Jesus’ family. It came halfway through a yearlong celebration of the family announced by Francis that is due to conclude in June with a big family rally in Rome.

Speaking at his studio window Sunday, Francis said he intended the letter to be his “Christmas present to married couples.” He urged them to keep having children to fight the “demographic winter” which, in Italy, has led to one of the lowest birthrates in the world.

“Maybe we aren’t born into an exceptional, problem-free family, but our family is our story — everyone has to think: It’s my story,” he said. “They are our roots: If we cut them, life dries up!”

Also Read | Pope holds Christmas Eve Mass as coronavirus surges in Italy

In the letter, Francis said lockdowns and quarantines had forced families to spend more time together. But he noted that such enforced togetherness at times tested the patience of parents and siblings alike and in some cases led to real difficulties.

“Pre-existing problems were aggravated, creating conflicts that in some cases became almost unbearable. Many even experienced the breakup of a relationship,” Francis wrote.

Also Read | In a blow to conservatives, Pope Francis wants to quash old Latin Mass

He offered his closeness to those families and reminded parents that the breakup of a marriage is particularly hard on children, who look to their parents as a constant source of stability, love, trust and strength.

“The breakdown of a marriage causes immense suffering, since many hopes are dashed, and misunderstandings can lead to arguments and hurts not easily healed,” he said. “Children end up having to suffer the pain of seeing their parents no longer together.”

He urged parents to keep seeking help to try to overcome conflicts, including through prayer. “Remember also that forgiveness heals every wound,” he said.

Also Read | Pope at 85: No more Mr Nice Guy, as reform hits stride

He repeated a refrain he has often used when meeting with families and married couples, listing the three most important words in a marriage: “Please, thanks and sorry.”

Picking up the theme in his remarks to tourists and passers-by in St. Peter’s Square, Francis said a failure to make peace before going to bed at night can lead to a “cold war” the next morning.

“How many times, unfortunately, conflicts originate within the domestic walls due to prolonged periods of silence and from unchecked selfishness!” he said. “Sometimes it even ends up in physical and moral violence. This lacerates harmony and kills the family.”

He urged families to put down their cellphones at the dinner table and talk. “It’s sad to see a family at lunch, each one with his or her own cell phone not speaking to one another, everyone talking to the mobile phone,” he said.

Also Read | Pope cites new book on nun abuse in warning to superiors

Then when an argument breaks out, each one repeats their refrains “staging a comedy they’ve already seen where everyone wants to be right and in the end a cold silence falls. That sharp, cold silence, after a family discussion, is ugly, so very ugly!” he said.

He urged parents to think not of themselves but others, and to pray “for the gift of peace.”