While the Ulma family were martyred on March 24, their feast day will be observed on July 7, the parents' wedding anniversary.
The entire Catholic Church rejoices at the beatification of the Ulma family on September 10, 2023. It will be the first time an entire family is beatified at a single celebration, as well as the only time in the history of the Church that an unborn child is beatified.
As it has been explained in other articles on Aleteia, “Jozef and Wiktoria Ulma and their seven children — including a baby who lost his life at birth — were executed on March 24, 1944, along with the Goldmanns, the Jewish family of eight they had been sheltering for a year and a half.”
Generally speaking, saints and beatified persons are honored in the liturgical calendar almost always on their date of death. Since saints are confirmed to already be in Heaven, the date of a saint’s death would be considered their “heavenly birthday,” or “entrance into Heaven.”
However, this is not always possible or desirable, for a variety of reasons, including if the saint’s death date may coincide with either another major feast, or the penitential season of Lent. In these two cases, their liturgical feast would never be celebrated.
An example of this situation is the feast of St. John Paul II. He died on April 2, 2005, which would fall during Lent or the first week of Easter. As a result, the Church assigned October 22 to be his feast, which is the anniversary of his elevation to the papacy.
Furthermore, in the case of the few married couples who have been recognized as blesseds or saints, their wedding anniversary is often chosen, such as Sts. Louis and Zelie Martin, whose liturgical feast is July 12.
The Ulma family’s feast day follows a similar pattern, as March 24 always falls during Lent and would make it difficult to have a joyous celebration.
The Church instead has chosen July 7 as their liturgical feast, as Jozef and Wiktoria were married on July 7, 1935. The postulator of their caused confirmed this date.
Initially this feast will only be celebrated in Poland. Local bishops would have to approve this feast to be included on their calendar, or the current pope could extend it to the universal Church after their future canonization.