Which Roman Catholic feast day gives Father's Day its date in Spain and Portugal?

In Spain and Portugal, Father's Day is associated with Saint Joseph's Day.

Saint Joseph's Day is observed on March 19 and honors Joseph, the husband of Mary and the traditional earthly father of Jesus in Christianity. Because Joseph is regarded as a patron of fathers and workers, the feast became a natural religious association for a celebration of fatherhood.

Spain's modern Father's Day tradition was promoted in the 1950s by Manuela Vicente Ferrero, a teacher better known by the pen name Nely. Portugal also observes Dia do Pai on March 19, linking the family holiday to the same feast day.

This is different from countries where Father's Day is scheduled by a weekday rule, such as the third Sunday in June. It is also more specific than saying the holiday falls on a saint's day: the relevant saint is Joseph, not Peter, Mark, or John. The March date is shared with the religious feast.