The pilgrimage will mark the 100th anniversary of the Marian apparitions, which began May 13, 1917, when 9-year-old Francisco and 7-year-old Jacinta, along with their cousin Lucia dos Santos, reported seeing the Virgin Mary. The apparitions continued once a month until Oct. 13, 1917, and later were declared worthy of belief by the Catholic Church.

A year after the apparitions, both of the Marto children became ill during an influenza epidemic that plagued Europe. Francisco died April 4, 1919, at the age of 10, while Jacinta succumbed to her illness Feb. 20, 1920, at the age of 9.

Francisco and Jacinta's cause for canonization was stalled for decades due to a debate on whether non-martyred children have the capacity to understand heroic virtues at a young age. However, in 1979, St. John Paul II allowed their cause to proceed; he declared them venerable in 1989 and beatified them in 2000.

The children's cousin entered the Carmelites. Sister Lucia died in 2005 at the age of 97. The diocesan phase of her sainthood cause concluded in February and now is under study at the Vatican.

The other canonizations set to take place Oct. 15 include:

-- The "Martyrs of Natal," Brazil, including: Blessed Andre de Soveral, a Jesuit priest; Blessed Ambrosio Francisco Ferro, a diocesan priest; Blessed Mateus Moreira, a layman; and 27 others. They were killed in 1645 in a wave of anti-Catholic persecution carried out by Dutch Calvinists.

-- Blessed Faustino Miguez, a Spanish priest and a member of the Piarist Fathers born in 1831. He started an advanced school for girls at a time when such education was limited almost exclusively to boys.

While he taught a variety of subjects and wrote numerous textbooks, he also honed an interest in botany, which led him to find a cure for a professor so ill that he was thought to be beyond hope. People then came to him from all parts of the country seeking relief from their sicknesses.

-- Blessed Angelo da Acri, an Italian Capuchin priest who was born Luca Antonio Falcone. A famed preacher, he was known for his defense of the poor. He died in 1739 and was beatified by Pope Leo XII in 1825.

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