Create a new WP_Query for the slider posts.
<div class="featured-rotator">
<?php $slide_query = new WP_Query( 'category_name=featured' );
if ( $slide_query->have_posts() ): ?><ul>
<?php while ( $slide_query->have_posts() ) : $slide_query->the_post(); ?>
<li class="post">
<div class="image"><?php the_post_thumbnail(); ?></div>
<h2><a href="https://wordpress.stackexchange.com/questions/145555/<?php esc_url( the_permalink() ); ?>" title="Permalink to <?php the_title(); ?>" rel="bookmark"><?php the_title(); ?></a></h2>
<?php if (get_post_meta($post->ID, "Author", true)): ?>
<span class="author">By <?php echo get_post_meta($post->ID, "Author", true); ?></span>
<?php endif; ?>
<?php the_content(__("Continue reading »")); ?>
</li>
<?php endwhile; ?>
</ul><?php endif; wp_reset_postdata(); ?>
</div>