A simple way of making sure not to display the same posts twice when using multiple loops. Save the post ID's into an array, then exclude those posts from future loops.

exclude_previously_looped_posts.php

<?php

//start a new WP_Query with whatever parameters you want
$firstquery = new WP_Query(array(
		'posts_per_page' => 2
		'tag' => 'summer'
	));

//start some looping action on $firstquery
while ($firstquery->have_posts()) : $firstquery->the_post();

//add the post ID to the array $excludeme
$excludeme[] = $post->ID; 

//do something, like include a post template
get_template_part('loop','feature');

//end the loop
endwhile;

//start a second WP_Query that exludes the post(s) we just looped
//note the double underscore in "post__not_in"
$secondquery = new WP_Query(array(
		'posts_per_page' => 5
		'tag' => 'summer',
		'post__not_in' => $excludeme
	));

//start some looping action on $secondquery
while ($secondquery->have_posts()) : $secondquery->the_post();

//do something, like include a post template
get_template_part('loop');

//end the loop
endwhile; ?>