"Taboo for the venerable, taboo for the relatives, taboo for the sage" - this phrase comes from "The Chun Qiu Gongyang Zhuan? Min AD Year", which was when Confucius compiled and deleted the "Spring and Autumn Annals" principles and attitudes. His principles and attitudes laid the foundation for traditional Chinese Confucian culture, and also destined that the word "equality" could not take root in China, let alone grow.
"Taboo for the venerable, taboo for the relatives" means that when we refer to the elders and other respected people, we should use taboos, especially when we need to mention their names.
If a child’s name contains characters from his parents’ names, even if they sound the same, it is disrespectful.