nesting error

The second unordered list should be nested in the list. The example code shows the list closing before the nested unordered list

fix: 
<ul>
      <li>Homer & Marge Simpson
          <ul>
            <li>Bart Simpson</li>
            <li>Lisa Simpson</li>
            <li>Maggie Simpson</li>
          </ul>
       </li>
      <li>Patty Bouvier (Twin)</li>

