Get all sub-labels of a Gmail label through a Google Script
<p>I would like to get all child labels of a given parent label. Is it possible?</p>

<p>In <a href="https://stackoverflow.com/q/30012268">How to check if a Gmail label has a nested sub-label?</a> it is checked whether all labels have a sub-label, and I tried doing something similar for an specific one, but with no results.</p>