Francisco and Jacinta Marto are the youngest of the seven children of Manuel Pedro Marto and Olimpia de Jesus, inhabitants of the parish of Fatima, in the municipality of Vila Nova de Ourém, in the Diocese of Leiria, Portugal.

Francisco was born on June 11, 1908 in his father's house, in Aljustrel, and was baptized on the 20th of the same month in the parish church of Fatima. His sister Jacinta was born on March 11, 1910, also in her parents' house, and was baptized on the 19th of the same month in the parish church.

They grew up in a family environment of modest means, in a quiet, agricultural town separated from a Portugal that was in political and social turmoil.

The brothers did not attend school. They could neither read nor write and had little knowledge of the geography, history and thought of the world beyond their mountains. Their Christian education was very simple: they learned catechism at home or with their aunt, the mother of their cousin Lucia who, together with them, would be one of the visionaries of Fatima.

Their parents also gave them an example of committed faith with their lives: Sunday participation in the Eucharist, family prayer, truth and respect for all, charity towards the poor and those in need. They began to take care of their parents' flock while still young: Francisco was 8 years old and Jacinta 6. They spent most of their days caring for the sheep, together with their cousin Lucia, also a shepherdess.

In 1916, in spring, summer and autumn, together with Lucia, they had the apparitions of the Angel of Peace. In 1917 they were visited by Our Lady of the Rosary, from May to October on the 13th of each month, except in August. In this month the apparition occurred on the 19th, since the Little Shepherds had remained in Ourém from 13 to 15 August 1917.

Francisco had a calm and peaceful character. He is remembered full of admiration for the creation in which he enjoyed the beauty of the Creator. The peace that he drew from this he then transmitted to his friends, among whom he knew how to be a sign of harmony, even when arguments or offenses occurred.

After the apparitions of the Angel and the Madonna, he developed a lifestyle characterized by adoration and contemplation. Whenever possible, he took refuge in some isolated place to pray alone. He often spent long hours in the silence of the parish church, near the tabernacle, to keep the hidden Jesus company. In his intimacy with God, Francisco glimpsed a God saddened by the suffering in the world, suffered with Him and wanted to console Him. The boy, who did not hear the voice of the Angel and the Lady, but only saw them, was the most contemplative of the three visionaries. In his life, it is evident how prayer is nourished by attentive listening to the silence in which God speaks. He allowed himself to be inhabited by the ineffable presence of God – "I felt that God was within me, but I did not know what it was like!" – and it is from this presence that he also welcomed others into his prayer. Francisco's life of faith was a life of contemplation.

In October 1918 he fell ill during an epidemic of bronchopneumonia. He progressively worsened until April 1919. On April 2nd he confessed and the following day he received the Viaticum in his home. The following day, April 4th, around 10:00 p.m., he died peacefully, at home, surrounded by his family.

He was buried in the cemetery of Fatima on April 5, 1919. On March 13, 1952, his mortal remains were transferred to the Basilica of Our Lady of the Rosary of Fatima.

Monsignor José Alves Correia da Silva, Bishop of Leiria, opens, on April 30, 1952, the Informative Process on the reputation of sanctity and virtues of Francisco Marto. The Process concluded on August 1, 1979. He was beatified by St. John Paul II on May 13, 2000 in Fatima, together with his sister Jacinta.