title: Require fieldset after checkbox checked
body: <p>I just started learning HTML/CSS, javascript and jQuery last week and would very much appreciate some help. 
  I have created a form with a checkbox (id #ship_to_billing) and then a fieldset (id #shipping_info) containing 5 text fields. Using JQuery I've set it up so that, if that if the checkbox is checked, it toggles the other fields and hides them. But, I cannot figure out how to additionally require one or the other, either the checkbox has to be checked or all of the text fields within the fieldset must be completed. I do not need an alert. Please help! </p>
  
  <p>Thank you all in advance, Susan</p>
  
  <pre><code>&lt;a type="button" class="btn btn-primary" href="#product-options" data-           
  toggle="modal"&gt;Buy This!&lt;/a&gt;                                        
      &lt;div class="modal hide fade" id="product-options"&gt;                    
          &lt;div class="modal-header center"&gt;
               &lt;a class="close" data-dismiss="modal"&gt;x&lt;/a&gt;
                  &lt;h3&gt;When, Where and How?&lt;/h3&gt;
           &lt;/div&gt;
              &lt;div class="modal-body l-m"&gt; 
              {% include 'datepicker' %}
              &lt;p&gt;
              &lt;input type="hidden" name="properties[ship_to_billing]" value="" /&gt;                          
              &lt;label for="ship_to_billing" style="max-width:335px;"&gt;
              &lt;input id="ship_to_billing" type="checkbox" name="properties[Ship to Billing Address]" value="Yes" {% if properties.ship_to_billing %} checked="checked"{% endif %} /&gt;
              &lt;font size=1&gt;Check here to have items shipped to your billing address (collected during checkout). Otherwise please fill out the information below.&lt;/font&gt;
              &lt;/label&gt;&lt;br /&gt; 
              &lt;/p&gt;                        
            &lt;div class="fieldgroup" id="shipping_info"&gt;
              &lt;label for="shipping_name"&gt;Name of Recipient:&lt;/label&gt;      
              &lt;input class="input-xlarge" type="text" id="shipping_name" placeholder="Name" name="properties[Recipient]" required="required" /&gt;                                 
              &lt;p&gt;
              &lt;label for="address_street"&gt;Shipping Address:&lt;/label&gt;
              &lt;input class="input-xlarge" type="text" id="address_street" placeholder="Street Address" name="properties[Address]" required="required" /&gt;
              &lt;input class="input-xlarge" type="text" id="address_city" placeholder="City" name="properties[City]" required="required" /&gt;
              &lt;input class="input-medium" type="text" id="address_province" placeholder="State" name="properties[State]" required="required" /&gt;
              &lt;input class="input-medium" type="text" id="address_zip" placeholder="Zip Code" name="properties[Zip]" required="required" /&gt;
              &lt;/p&gt;
            &lt;/div&gt;
            &lt;p&gt;
            &lt;label for="gift_msg"&gt;Gift Message :&lt;/label&gt;                                
            &lt;textarea id="gift_msg" placeholder="Please type your message" name="properties[Gift Message]" rows="4" cols="45"&gt;&lt;/textarea&gt; 
            &lt;/p&gt;                              
         &lt;/div&gt;
  
         &lt;div class="modal-footer"&gt;
             &lt;div class="btn-group"&gt;
                  &lt;button href="#" class="btn" data-dismiss="modal"&gt;Cancel&lt;/button&gt;
                  &lt;button type="submit" onclick="return validateShipping();" class="btn btn-primary" id="addtocart"&gt;Add To Cart&lt;/button&gt;
              &lt;/div&gt;
            &lt;/div&gt;              
          &lt;/div&gt;
  </code></pre>
  
  <p>JQUERY:</p>
  
  <pre><code>&lt;script&gt;
  $('#ship_to_billing').change(function(){
  $('#shipping_info').toggle('show');
  });
  &lt;/script&gt;
  </code></pre>