Just add 'post__in' => get_option('sticky_posts')
to your query, to confine your query to only sticky posts. So,
$getHighlights = array(
'numberposts' => 7,
'post_type' => array('post','Event'),
'post__in' => get_option('sticky_posts'),
'category_name' => 'Highlights'
);
should work for you.
Edit: This is how you can merge two arrays to get the sticky posts at the top of your query:
$getHighlights_sticky = get_posts( array(
'numberposts' => 7,
'post_type' => array('post','Event'),
'post__in' => get_option('sticky_posts'),//it should be post__in but not posts__in
'category_name' => 'Highlights'
));
$getHighlights_other = get_posts( array(
'numberposts' => 7 - count( $getHighlights_sticky ),
'post_type' => array('post','Event'),
'post__not_in' => get_option('sticky_posts'),//it should be post__not_in but not posts__not_in
'category_name' => 'Highlights'
));
foreach ( array_merge( $getHighlights_sticky, $getHighlights_other ) as $post ) {
setup_postdata( $post );
// your display loop
}
This will show 7 posts, with the stickies at the top (of course, this is assuming you don’t have more than 7 stickies, otherwise it’ll be all messed up…) (edited to use numberposts
as per OP’s comment below…)