JSFiddle - React, Tailwind, and code Playground

HTML

<input type="checkbox" name="supplied" id="supplied" value="supplied" class="aboveage2" />
  <input type="checkbox" name="supplied" id="supplied_1" value="supplied" class="aboveage2" />
  <input type="checkbox" name="supplied" id="supplied_2" value="supplied" class="aboveage2" />
  <input type="checkbox" name="supplied" id="supplied_3" value="supplied" class="aboveage2" />
  <input type="checkbox" name="supplied" id="supplied_4" value="supplied" class="aboveage2" />
  <input type="checkbox" name="supplied" id="supplied_5" value="supplied" class="aboveage2" />

<ul id="date" style="display:none">
    <li><input id="start" name="start" size="5" type="text" class="small" value="1" /></li>
    <li><input id="end" name="end" size="5" type="text" class="small" value="2" /></li>
</ul>

JavaScript

$('.aboveage2').live('change', function(){
      var $inputs = $(this).siblings('input').add($(this));
      var checked = false;
      for (var i = 0; i < $inputs.length; i++) {
         var input = $inputs[i];
         checked = $(input).is(':checked');
        if (checked) break;
      }
      $('#date').toggle(checked);
 });