'Offspring' in the Bible

Then Haman told Zeresh his wife and all his friends everything that had happened to him. Then his wise counselors and his wife Zeresh said to him, “If Mordecai, before whom you have begun to fall in status, is of Jewish heritage, you will not overcome him, but will certainly fall before him.”

The letters were sent in the name of King Ahasuerus and stamped with his ring, and they were taken by men on horseback, going on the quick-running horses used for the king's business, the offspring of his best horses:

the Jews established and adopted [it] for themselves and for their offspring, and for all who joined them. They did not neglect {to observe} these two days every year as it was written and appointed to them.

These days [are] to be remembered and [are] to be kept in every generation, and in family, province, and city; and these days of Purim are not [to be] neglected among the Jews, and their memory shall not come to an end among their offspring.

to establish these days of Purim at their appointed times, just as Mordecai the Jew and Queen Esther had imposed, and just as they had imposed on themselves and their offspring regulations of the fast and their lament.