Some people believe that a man's fate can be predicted when he is only a 3 years old.child.I think ,it makes sense to some extent.my question is how to say the meaning in a simple way?
You could quote Wordsworth:

My heart leaps up when I behold
A rainbow in the sky:
So was it when my life began;
So is it now I am a man;
So be it when I shall grow old,
Or let me die!
The Child is father of the Man;
I could wish my days to be
Bound each to each by natural piety.


Virgil said As the twig is bent the tree inclines, meaning the person's character is formed at an early age.

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Thanks a lot!
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