Add help text to radio button when it's disabled I have two radio button groups that have a dependency.

When Button 1 is clicked, Buttons 4 and 5 should be disabled and vice versa. If Button 2 is clicked Button 4 and 5 are active and Button 3 is disabled.

How can I add help text to the disabled buttons that states the buttons are disabled because of your selection in Group A (Organization).

Here is the javascript that handles the buttons. 

$(document).on('click', function () {
    // Organization and Data Classification dependency
    if($('#edit-field-organization-und-0').is(':checked')){

        $('#edit-field-data-classification-und-public').attr('disabled',false);     
        $('#edit-field-data-classification-und-internal').attr('disabled',false);           
        $('#edit-field-data-classification-und-confidential').attr('disabled',false);                       

        $('#edit-field-data-classification-und-btn1').attr('disabled',true);    
        $('#edit-field-data-classification-und-btn1').removeAttr('checked');            
        $('#edit-field-data-classification-und-btn2').attr('disabled',true);
        $('#edit-field-data-classification-und-btn2').removeAttr('checked');

    }
    else{
        $('#edit-field-data-classification-und-public').attr('disabled',true);  
        $('#edit-field-data-classification-und-public').removeAttr('checked');      
        $('#edit-field-data-classification-und-internal').attr('disabled',true);    
        $('#edit-field-data-classification-und-internal').removeAttr('checked');            
        $('#edit-field-data-classification-und-confidential').attr('disabled',true);
        $('#edit-field-data-classification-und-confidential').removeAttr('checked');

        $('#edit-field-data-classification-und-btn1').attr('disabled',false);           
        $('#edit-field-data-classification-und-btn2').attr('disabled',false);

    }


}

enter code here
I would suggest you might want to think about using the Conditional Fields module and having two separate fields for the change in Group B.

But for this specific question-- not knowing your HTML structure exactly -- you'd likely just be adjusting the HTML of the label. And that would then be more of a JS design question than a drupal one (unless you are building a modue around the idea) ... how to do that best depends on how re-usable you'd want it. In straight up JS: I'd likely store a hashed array of the label text, then have arrays of the option b input radio button ids -- one for option a1, the other for option a2. And then have a function that works on the appropriate array, passing in whether it should be enabled for not: foreach optionba1; change state, unselect anything checked, change text (return to original or add new text).