using firstchild in jquery code example

Example 1: firstElementChild jquery equivalent

$('#myList > li:first-child');
// or
$('#myList').children('li:first-child');
// or
$('#myList > li').first();
// or
$('#myList').children().first();
// and so on

Example 2: jquery first child

$( "li" ).first().css( "background-color", "red" );