JSFiddle - React, Tailwind, and code Playground
HTML
<div id='center'>
<div id='first'>1</div>
<div id='second'>2</div>
</div>
JavaScript
$('#center').find('div').each( function(){alert($(this).attr('id'))})
<div id='center'>
<div id='first'>1</div>
<div id='second'>2</div>
</div>
$('#center').find('div').each( function(){alert($(this).attr('id'))})