Sisters-in-law Princess Caroline and Princess Charlene pay their respects to Pope Francis

Royals around the world have been paying tribute to Pope Francis' since his passing. On Tuesday, Prince Albert and Princess Charlene of Monaco attended a pontifical mass at Monaco Cathedral in honor of the late pontiff. The royals were accompanied by Albert's older sister, Princess Caroline, at the service, which the Prince's Palace noted "brought together the highest Monegasque authorities and many faithful, in a profound moment of reflection and shared emotion." 

The royal sisters-in-law were both dressed in black for the occasion, while Prince Albert sported a blue suit with a black tie. The Prince's Palace shared photos from the mass, showing Charlene sitting between her husband and sister-in-law at the service. It was announced on Tuesday that Albert had decreed three days of national mourning would be observed in the Principality of Monaco, starting Thursday through Saturday, the day of Pope Francis' funeral. The Prince also ordered that flags be flown at half-mast on public buildings from Monday, April 21, until the end of the funeral. 

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Following His Holiness' death on Monday (April 21), Albert referred to the late pope as a "very great servant of mankind." In a statement, Grace Kelley's son said (translated to English): "It is with infinite sadness and deep sorrow that we learned of the death of His Holiness Pope Francis on this Easter Monday. Particularly moved, my family, myself and the Principality would like to express our deepest condolences to the Catholic Church and all the faithful with whom we share a great sorrow. In this time of pain and mourning, we keep in mind and in our hearts the apostolic blessings which the Holy Father lavishly bestowed upon us during his Pontificate and fervently pray for the repose of his soul."

"May his unrelenting message of love, brotherhood, peace, faith, justice, mercy, compassion, and respect for our nature continue to nourish our thoughts and commitments to the service of the common good and radiate upon a world he will leave his mark on," the Prince continued. "With profound gratitude, we pay tribute to the very great servant of mankind who has just left us. We ask Your Eminence Reverendissime to want to believe well in the part that we take, along with all the inhabitants of the Principality, in the mourning of the Church and the Vatican City."

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Prince Albert and Charlene, who converted to Catholicism ahead of her 2011 wedding to Albert, attended Pope Francis' inaugural mass at the Vatican back in 2013, and met with the 266th pontiff in 2016 and 2022. In a past interview with Paris Match Charlene admitted that the values of Catholicism "correspond perfectly" to her spirit.  

“According to Grimaldi tradition, Catholicism is the state religion [in Monaco]. But for me it represents much more," the Princess said, via PEOPLE. “The values of this religion profoundly touch me and correspond perfectly to my spirit. In January 2013, Prince Albert took me to the Vatican to present me to [Pope Francis's predecessor] Pope Benoit XVI, just as Prince Rainier did with Grace Kelly and Pie XII. That experience was extremely intense and moving for me.”