JSFiddle - React, Tailwind, and code Playground

HTML

<div id="validDiv01">
    <input />
    <input />
    <input />
</div>
<hr />
<div id="validDiv02">
    <input />
    <input />
    <input />
</div>
<hr />
<div id="validDiv03">
    <input />
    <input />
    <input />
</div>

JavaScript

function ISeeWhatYouDidThere(e) {
    var $repeat = 0,
        $val = e.val(),
        $parent = "#" + e.closest("div").attr("id")
    ;
    if($.trim($val) == "")
        return;
    e.removeClass("ui-state-error");
    $("input", $parent).each(function() {
        if($(this).val() == $val)
            $repeat++;
    });
    if($repeat <= 1)
        return;
    alert("Repetido!");
    e.addClass("ui-state-error");
}
/////////////////////////////////
$("input","div").blur(function(){
    ISeeWhatYouDidThere(
        $(this)
    );
});