JSFiddle - React, Tailwind, and code Playground

HTML

<form action="saveresponse.php" method="POST" name="mainForm">
    <input class="cbox_yes" type="checkbox" name="yes" value="01.jpg" /> OK
    <input class="cbox_sp" type="checkbox" name="sp1" value="01.jpg" disabled />Special<br />
    <input class="cbox_yes" type="checkbox" name="yes" value="02.jpg" /> OK
    <input class="cbox_sp" type="checkbox" name="sp2" value="02.jpg" disabled />Special<br />

JavaScript

$('input[type="checkbox"]').click(function(){
    var obj = $(this);
    if(obj.is(':checked')){
        obj.next('.cbox_sp').attr({'checked':'checked', 'disabled':false});
    }else{
        obj.next('.cbox_sp').attr({'checked':false, 'disabled':true});        
    }
});