Showing sticky posts with get_posts()

I’m using this to retrieve posts on my index page:

<?php $posts = get_posts( "category=13&numberposts=2" ); ?> 
<?php if( $posts ) : ?>
<?php foreach( $posts as $post ) : setup_postdata( $post ); ?> 

[code]

Is there a way to include sticky posts on loops like that one? Or I’ll have to use WP_Query?