I don’t think your question displays a good understanding of narcissism. There is no ‘choice’ involved in being a narcissist. Narcissism is a mental illness. People do not ‘choose’ to get Covid or ‘choose’ to be born with spina bifida or ‘choose’ to be born with blue eyes. People do not ‘choose’ to ‘become’ a narcissist. It is an inborn defect in brain structure, or a defect in brain development brought on by trauma.
Furthermore, a 4 year old child is not capable of the kind of high level thinking that would inform their adult identity. How many people do you know who said “I’m going to be an astronaut when I grow up” at age 4 who are astronauts now? It’s more correct to say that either brain damage or abuse, or some combination of both, causes a person not to be able to advance past the emotional development of a 4 year old—so a person may be 40 years old with the book learning intelligence and vocabulary of a 40 year old but emotionally they are still in the state of a 4 year old child—impatience, selfishness, temper tantrums, etc. They may have adult physical desires and adult intellect, but emotionally they remain children over their entire lifetime. It’s not a choice a person makes.
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