JSFiddle - React, Tailwind, and code Playground

HTML

<div id="ParentDiv">
    <div id="ChildDiv">
        <ul>
            <li>1</li>
            <li>2</li>
        </ul>
    </div>
    <!-- move SomeDiv here -->
</div>
<div class="SomeDiv">some content</div>

JavaScript

document.getElementById('ParentDiv').appendChild(document.getElementsByClassName('SomeDiv'));