Vatican, Pope Francis visits Ratzinger for Christmas greetings

It is a gesture of courtesy that is renewed every year and which testifies to the friendship and mutual respect between the two Pontiffs

Pope Francis went to the Mater Ecclesiae Monastery in the Vatican to wish Pope Emeritus Benedict XVI a Christmas. This was announced by the Holy See press office. It is a gesture of courtesy that is renewed every year and which testifies to the friendship and mutual respect between the two pontiffs.
Source: https://www.tgcom24.mediaset.it/cronaca/lazio/vaticano-papa-francesco-fa-visita-a-ratzinger-per-gli-auguri-di-natale_3181845-201802a.shtml