一人得道鸡犬升天

一人得道，鸡犬升天:

Literally means:

when a man attains the Tao (enlightenment and immortality), his family as well as his pets ascends to heaven; when a man gets to the top, all his relatives also rise to power

Actually means:

According to an ancient legend, a man named Liu An became an immortal after practicing Taoism. When his whole family ascended to heaven, they scattered the left magic pills in his courtyard. His chickens and dogs ate them, and ascended to heaven, too.

It figuratively means that when a man is promoted to a powerful position, all those that are related to him benefit. Derogatory

传说古代有个叫刘安的人修炼成仙，全家升天时，把用剩的丹药撒在院子里，他家的鸡和狗吃了药也一起升上了天。

比喻一个人做官有了权力，和他有关系的人也一起跟着得到好处。具有贬义色彩。