Vatican City — Pope Francis has approved a miracle so that for the first time, a married couple can be canonized together.

The canonization ceremony for Blessed Louis and Zelie Martin, the parents of St. Therese of Lisieux, is likely to take place during the world Synod of Bishops on the family in October.

Pope Francis signed the decree Wednesday, the Vatican said, although it provided no details about the miraculous cure said to have taken place through the couple's intercession.

However, the promoters of the sainthood cause said the miracle being studied involves a little girl in the archdiocese of Valencia, Spain. Born prematurely and with multiple life-threatening complications, Carmen suffered a major brain hemorrhage, which could have caused irreversible damage. Her parents prayed for the Martins' intercession. The little girl survived and is healthy.

Cardinal Angelo Amato, prefect of the Congregation for Saints' Causes, had said in late February that "thanks be to God, in October two spouses, parents of Saint Therese of Lisieux, will be canonized."

Blessed Louis and Marie Zelie Guerin Martin were married in 1858. The couple had nine children, but four of them died in infancy. The five who survived -- including St. Therese -- all entered religious life. Zelie Martin died of cancer in 1877 at the age of 45; her husband died when he was 70 in 1894.

The couple was beatified in 2008. They are believed to be the first parents of a saint to be beatified, highlighting the important role parents play in their children's human and spiritual upbringing.

The next step toward canonization is for the pope to hold a consistory with cardinals present in Rome to announce the decision to proceed with the ceremony during the world Synod of Bishops on the family Oct. 4-25. A Vatican official said that meeting probably would be in June.

Before opening the October 2014 meeting of the extraordinary Synod of Bishops on the family, Pope Francis venerated the relics of St. Therese, her parents and another couple, Blessed Luigi and Maria Beltrame Quattrocchi; the relics were brought to Rome specifically for prayers during the bishops' discussions about family life.