A French bishop has officially opened the beatification Cause of Léonie Martin, the sister of St Thérèse of Lisieux. Bishop Jean-Claude Boulanger of Bayeux-Lisieux opened the diocesan stage of the Cause on Saturday at a Mass at the Monastery of the Visitation in Caen, north-west France, where Léonie lived from 1899 until her death in 1941, aged 78. Léonie, who took the name Sister Françoise-Thérèse when she entered religious life, now has the title "Servant of God". Léonie, the third of the five surviving children of the Martin family, had a difficult childhood. According to a website dedicated to her life, she was often ill, was physically abused by a maidservant, was expelled from school and was isolated within the family. She attempted to enter religious life three times before she was accepted at the monastery in Caen. She was known as the "forgotten sister" of St Thérèse. But her life story began to receive attention when Marie Baudouin-Croix published the book Léonie Martin: A Difficult Life in France in 1989. A website highlighting the holiness of the five Martin sisters says that St Thérèse wrote her last letter to Léonie on July 17 1897, a few months before her death, encouraging her sister to become a saint. She wrote: “If you want to become a saint, it will be easy, because in the depths of your heart the world means nothing to you … I mean that while you give yourself devotedly to external works, you have but one goal: to give pleasure to Jesus and to be united more intimately with Him.”