The Mysqli query does not work twice

I cannot get my Mysqli queries to both work. If I comment out one function in my html, the other function is properly executed and vice versa.

function all_posts() {
    require_once 'database.inc.php';
    $mysqli = mysqli_connect($host, $username, $password, $database);
    $query = mysqli_query($mysqli, "SELECT variable_name, post_name, post_date, post_display FROM blog_posts ORDER BY id DESC LIMIT 5");

    if (!$query)
        echo mysqli_error();

    while ($results = mysqli_fetch_assoc($query)) {

        $post_name = $results['post_name'];
        $post_date = $results['post_date'];
        $post_display = $results['post_display'];
        $variable_name = $results['variable_name'];

        echo "<a href='posts.php?post={$variable_name}'>";
        echo "<div class='entry'>";
        echo "<div class='entry_header'>";
        echo "<h2>{$post_name}</h2>";
        echo "<h3>{$post_date}</h3>";
        echo "</div>";
        echo "<p>{$post_display}</p>";
        echo "</div>";
        echo "</a>";
    }

    mysqli_free_result();
}

function all_sidebar_posts() {

    require_once 'database.inc.php';
    $mysqli = mysqli_connect($host, $username, $password, $database);
    $query = mysqli_query($mysqli, "SELECT variable_name, post_name FROM blog_posts ORDER BY id DESC LIMIT 5");

    while ($results = mysqli_fetch_assoc($query)) {

        $post_name = $results['post_name'];
        $variable_name = $results['variable_name'];
        echo "<li><a href='posts.php?post=$variable_name'>$post_name</a></li>";
    }

    mysqli_free_result();
}

Here is the html that I am outputting to.

<ul>
    <?php all_sidebar_posts(); ?>
</ul>
</div>
<div class="content_container">
    <?php all_posts(); ?>
</div>

I have tried using mysqli_data_seek(); but haven't had luck. Perhaps I am not using it right? I have browsed many questions and found similar ones but I have tried them all to no avail. I am new to programming so I may be overlooking something basic. Thank you all for the help!

---

You are doing it wrong way.
Never mix your data manipulation code with presentation code.

First make a function to get posts:

function get_posts() {
    global $mysqli;
    $sql = "SELECT variable_name, post_name, post_date, post_display
            FROM blog_posts ORDER BY id DESC LIMIT 5"
    $result = mysqli_query($mysqli, $sql);
    if (!$result) trigger_error(mysqli_error()."[$sql]");
    $date = array();
    while ($row = mysqli_fetch_assoc($result)) {
        $data[] = $row;
    }
}

call it this way

require_once 'database.inc.php';
$mysqli = mysqli_connect($host, $username, $password, $database);
$data = get_posts();

and then use this array to display