The post, WHAT OTHERS SAY MATTERS (April 17, 2023), suggested you write down things you often heard said about yourself at any age as a child or as an adult. Using only positive things you remember hearing, write down when and how you have proved that those things are correct. For example, if you often heard you are smart, you might write about the time you did a smart thing to avoid a fight with your boss.
It is your actions that show what you have heard about yourself is true and proves who you are. Believe it.
If the children you care about are old enough, offer them a positive characteristic that you believe they have and then help them think what actions of theirs “prove” the characteristic is true.