The director of the Holy See's Press Office, Father Federico Lombardi, told reporters the celebrations began in the morning at the former pope's Vatican residence, Mater Ecclesia.
Archbishop Georg Gaenswein, prefect of the papal household and personal secretary of Benedict XVI, concelebrated at the Mass which was attended by close friends and Benedict XVI's “family” of religious women from Communion and Liberation's consecrated lay order Memores Domini.
The celebrations continued with a Bavarian style breakfast and joyful song. At 5:45 p.m., the Ratzinger brothers attended a music concert in honor of Monsignor Ratzinger at the studios of Vatican Radio, featuring piano, violin and a tenor singer.
The prefect of the Congregation for the Doctrine of the Faith, Archbishop Gerhard Ludwig Mueller – who worked with Msgr. Ratzinger when he was director of the choir at the Cathedral of Ratisbona – also attended the concert.
Retired pontiff Benedict XVI celebrated his brother Monsignor Georg Ratzinger's 90th birthday on Jan. 15 at the Vatican with a sung Mass and a simple concert.
Benedict XVI, Celebrations