How to determine the age of the eldest boy, middle boy and young boy in the "Book of Changes"?

In the "Book of Changes", the eldest man, the middle man, and the young man are ranked. Age is not absolute, it is all relative.

The eldest boy is the eldest boy, the middle boy is the second eldest boy, and the younger boy is the third eldest boy.

If you calculate the marriage in the hexagram, you will find the eldest boy and the girl, that is, "Leize returns to his sister".

It can be determined that the man is older or he is the eldest at home. This depends on the judgment of the person who predicts the prediction.

Extended information:

In the Book of Changes, Qian is the father and Kun is the mother. Zhen is the eldest boy, Kan is the middle boy, and Gen is the young boy. Xun is the eldest daughter, Li is the middle daughter, and Dui is the maiden.

The Plum Blossom Yi Number pays special attention to the heart changes. For example, if a woman is testing her marriage, the main hexagram will be up and down. The shock can be the eldest son or a young man. Two pairs face each other, if the woman is a young woman, then Zhen represents a young man.

The traditional Chinese Book of Changes introduces that a woman’s menstrual cycle has changed from seven to forty-nine, which is related to the changes in all things in the world. A baby will go through a seven-day development cycle in the mother's womb. After reaching the fortieth stage, the baby will be born and then begin a seven-year growth cycle.

So, 7 is a very mysterious number in Bagua. In Yi Xue, the age difference between men and women at marriage is also introduced.

Baidu Encyclopedia - I Ching (philosophy book)