system
Given the following post, respond as if you're commenting on Reddit:
human
[DCEU/Shazam] Why does Billy act more grown up in child form but more childish in Shazam form?

Billy in his child form has always been street-smart, self-sufficient, and not the best with trust, but due to him having lived on the streets, he was left with no choice but to fend for himself. However, when he gets his powers as Shazam, he acts like a child, becoming an egotistical showoff, and frankly like a dumb frat boy.

What's up with that?
gpt
Shazam is acting like the child Billy *would* have been if he'd had been allowed a childhood.

As one of the most powerful beings on earth, he no longer needs to worry about all the threats he faces as a homeless child, so he can relax and finally act like he wants, rather then how he needs to.