In the Roman Catholic Church, women who have been married and have been mothers are allowed to become nuns if they are widows. If a woman has been divorced and wants to become a nun, she must go through a religious evaluation process for her marriage to be annulled.
This means that the marriage, which is a sacramental contract between two people and God, is dissolved. If she receives an annulment, then she can become a nun. This is also true for a man if he wants to become a priest, monk, or brother.
However, if there are children involved, their care takes priority over all. The divorced or widowed mother or father must wait until the children reach adulthood. They must complete their parental responsibility before they can be considered for religious life. Each religious order or community might have their own rules on this and there might be exceptions, but this is the basic philosophy for all.
We apologize to our readers that we didn’t answer this question correctly.