Question:
Answer:
Divorce alone was never a cause for excommunication. Divorce and remarriage without an annulment did have the potential for penalties.
In 1884, the United States Catholic bishops established a regional law that automatically excommunicated those who divorced and remarried without an annulment. It did not affect those who were only divorced, and it definitely did not excommunicate any children from the marriage. This law applied only to Catholics in the United States.
The universal 1917 Code of Canon Law, which would have been in place in the early 1960s, did not contain a penalty of excommunication for those who were divorced. Nor were the children of the divorce excommunicated.
The 1917 Code did allow for the excommunication of those who divorced and remarried without an annulment (canon 2356). However, this excommunication was not automatic. The bishop had to formally excommunicate the individual. The bishop first had to warn the person to separate from their civil marriage spouse, and if the person refused, the bishop was then to excommunicate the person. But this would not have applied to the children.
Even if your mother had been divorced and civilly remarried and either automatically or formally excommunicated, it would have been a moot point by 1977. In 1977, Pope Paul VI rescinded and halted all excommunications for the divorced and civilly remarried.