Question

<div class="second">
    <div class="selector" id="selFirst"></div>
    <div class="selector" id="selSecond"></div>
    <div></div>
</div>

How to get #selFirst using element index not the ID?

this:

var $selFirst = $(".second:nth-child(1)");
console.log($selFirst);

is returning :

jQuery(div.second)

Answer 1

If you know the child element you’re interested in is the first:

 $('.second').children().first();

Or to find by index:

 var index = 0
 $('.second').children().eq(index);