Why does your online Saint of the Day feature have a different saint for that day compared to other books or websites?
Our Saint of the Day online feature is based on the Roman (worldwide) calendar, but we cannot follow that exactly for two reasons:
Sometimes the Church has two or more unrelated saints on the same day (e.g., August 2—Sts. Peter Julian Eymard and Eusebius of Vercelli).
There are many days for which the Roman calendar has not assigned a saint (e.g., August 3).
In the first case, we move one of the saints (usually the more recent one) to a day on which no one has been assigned—as identified in the second case.
In addition, the Church has approved liturgical calendars for specific countries, dioceses, and religious communities. For example, before Blessed John Paul II was canonized, celebrating his feast was authorized for October 22—but only for Poland, Italy, the United States, and any other country that had requested this permission. In such cases, Saint of the Day online follows the calendars approved for the United States, Canada, and Mexico. In the case of religious communities such as the Order of Friars Minor, Saint of the Day online uses the day assigned in the calendar approved by the Holy See for feasts not on the Roman calendar.
I realize this may sound confusing, but because of the two reasons mentioned, that’s the best we can do because this feature is called Saint of the Day.