JSFiddle - React, Tailwind, and code Playground

HTML

<div id='wrapper'>
    <a class="myselector" rel="I need this value"></a>
    
    <div class="someClass" id="someID">
        ...bunch of elements/content
        <input type="button" name="myInput" id="inputID" value="myinput" title="myInput Title" />
        ...bunch of elements/content
    </div>
</div>

JavaScript

$('#inputID').live('click',function(){
  // alert($(this).parent().parent().html());
alert($(this).parent().parent().find('a.myselector').attr('rel'));
});