There is no "feast" day on April 1. A feast is the second rank for a holy day in the Catholic Church. There are no solemnities nor memorials scheduled for that day in the Roman calendar. However, the following Saints and Blesseds may be remembered on 1 April:
St. Melito of Sardis
St. Venantius
St. Victor and Stephen
St. Walericus
St. Theodora
St. Caidoc & Fricor
St. Cellach
St. Dodolinus
St. Hugh of Grenoble
St. Macarius the Wonder-Worker
St. Quintian and Irenaeus
St. Melito of Sardis
Bl. Anacleto González Flores
Bl. Ludovico Pavoni
There is no saint named Isabel with a feast day of September 1.
If you are referring to Saint Aaron of Brettany, his feast day is June 22.If you are referring to Saint Aaron of Caerleon, his feast day is July 1.
The feast day of Peregrinus Laziosi is May 1.
November 1 is the feast day of Rachel the Matriarch.
Saint Eligius: Feast Day/Memorial: December 1 Saint Dunstan: Feast Day/Memorial: May 19
The feast day of St. Therese of Lisieux is October 1.
The feast day of St. Therese of Lisieux is October 1.
The feast day of Saint Peregrine Laziosi is May 1.
The feast of St. Brigit of Ireland is February 1.
The feast of Saint Sofia (or Sophia) is on August 1.
March 19 is the feast of St. Joseph, patron saint of families, fathers, and of Italy. May 1 is the feast of Saint Joseph the Worker.
December 1