JSFiddle - React, Tailwind, and code Playground

HTML

<div class="parent">
    <input class="childInput" type="text" />
    <div class="sibling"></div>
</div>

CSS

.parent {background: green}
.focused {background: red;}

JavaScript

$('.parent > *')
    .focus(function() {
        $('.parent').addClass('focused');
    })
    .blur(function() {
        $('.parent').removeClass('focused');
    });