You can make it with jQuery a less lines:
$(function(){
var requiredCheckboxes = $(':checkbox[required]');
requiredCheckboxes.change(function(){
if(requiredCheckboxes.is(':checked')) {
requiredCheckboxes.removeAttr('required');
}
else {
requiredCheckboxes.attr('required', 'required');
}
});
});
With $(‘:checkbox[required]’) you select all checkboxes with the attribute required, then, with the .change method applied to this group of checkboxes, you can execute the function you want when any item of this group changes. In this case, if any of the checkboxes is checked, I remove the required attribute for all of the checkboxes that are part of the selected group.
I hope this helps.
Farewell.