Fr. Marco Billeri, a 41-year-old priest from the Diocese of San Miniato, has a doctorate in canon law and experience in various parish and diocesan roles.

Pope Leo XIV has appointed Father Marco Billeri to serve as his second private secretary. The Italian diocese of San Miniato in Tuscany, where the 41-year-old priest is incardinated, announced the appointment on September 27, 2025. Father Billeri, who has a doctorate in canon law, will assist the new pope on a daily basis alongside the first secretary, Father Edgard Iván Rimaycuna Inga.