All nouns which are modified by "true" can exist only together with shimjeong. The term "true filial child" is used together with shimjeong.
Quotes about filial piety
From the speeches of Sun Myung Moon and Hak Ja Han
A child of filial piety should feel ashamed of not being able to give something better to his parents, though he actually brought the best possible thing to them.
We should be in the position of the older son and stop mankind from being whipped.
When you have no condition of accusation from Satan, God can regard you as His son and command you.
It may be natural that children die without fulfilling their responsibility. But God must overcome that situation when He sees it. We have to know how miserable such a God is and console Him in His sorrow.
A rebellious word from a child of filial piety is more painful to the parent than a thousand rebellious words from an unfilial child.
A child acts after he explores his parents' shimjeong by himself.
Children of filial piety are those who feel a parental shimjeong. It doesn’t matter what worldly knowledge or position you have. The only thing that matters is whether you have the shimjeong of heaven.
A person who loves his or her family is called a filial son.
You can serve God with all your sincerity, not because you have learned it from someone who guides or forces you, but because that kind of feeling automatically springs forth from your shimjeong.