JSFiddle - React, Tailwind, and code Playground

HTML

<input id="a" value=a>
<input id="b" value=b>

    <br/>^ focus on the input<br/><br/>

CSS

#b {display:none;}

JavaScript

$("#a").focus(function(){
    $("#b").show();   
});

$("#a, #b").blur(function(){
    $("#b").hide();
});

$("#b").focus(function(){
    $("#b").show();   
});