JSFiddle - React, Tailwind, and code Playground

HTML

<div id='parent-div'>
    <div id='child-div'>
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    </div>
</div>

CSS

#parent-div{
min-height:400px;
width:250px;
background-color:#333;
position:relative;
}


#child-div{
position:absolute;
height:auto;
top: 0%;
}

JavaScript

$().ready(function(){
    ch = $('#child-div').height();
    $('#parent-div').css({
        height : ch + 50 + 'px'
    })
});