The words of our Sages are well-known, when they said that the main products of the righteous are their good deeds. It also says that one who does one mitzva makes for himself provides himself with one advocate which is an angel created from Mitzvos. It is better for a person “to give birth” to an angel, who will advocate good for him, than to give birth to a son of flesh and blood who may sin.
An angel who can act as his advocate will be more effective for his soul than a son of flesh and blood. Therefore, a person should reflect and see how much people invest in order to set up generations of flesh and blood, and he should make a “kal vachomer” for himself how much he should invest to set up the main “children” which are good deeds.