JSFiddle - React, Tailwind, and code Playground

HTML

<div>    
    <div class="child"></div>
    <div class="child">x</div>
    <div class="child">x</div>
    <div class="child">x</div>
    <div class="child">x</div>
    <div class="child">x</div>
    <div class="child">x</div>
    <div class="child">x</div>
</div>

CSS

.childWrapper {
    background-color: red;
}

JavaScript

function wrapDivs(number) {
        var divs = $("div > div");
        for(var i = 0; i < divs.length; i+=number) {
            divs.slice(i, i+number).wrapAll("<div class='childWrapper'></div>");
            //alert("");
        }
    }

wrapDivs(1);