Get USER ID in user_register action

Hi guys, I am having trouble of getting the ID in user_register filter in functions.php…

Here is what I got

add_action( 'user_register', 'sendanotheremail' );
function sendanotheremail($user_id) {
        $user = new WP_User($user_id);
        $user_login = stripslashes($user->user_login);
        $user_email = stripslashes($user->user_email);
        $get_id      = $user->ID;
        global $wpdb;
        $getunion = $wpdb->get_results("SELECT value from wp_bp_xprofile_data where user_id = $get_id AND field_id = 4", "ARRAY_N");
        $message  = sprintf(__('New user registration on %s:'), get_option('blogname')) . "\r\n\r\n";
        $message .= sprintf(__('Username: %s'), $user_login) . "\r\n\r\n";
        $message .= sprintf(__('E-mail: %s'), $user_email) . "\r\n";
        $message .= "<br /> Please go here to approve the new user <a href=\"http://xxx.com/wp-admin/admin.php?page=bp_registration_options_member_requests\">Approve/Deny</a>";
        if(!($getunion)) {
                $message .= "nothing there";
        }
        else {
                $message .= "yes";
        }
$headers = 'From: xxx <xxx@xxx.com>';
add_filter('wp_mail_content_type',create_function('', 'return "text/html";'));
wp_mail('xxx@xxx.com', 'New User Registration to xxx website', $message, $headers);
}

I am testing the getunion if its empty I am returning “nothing there”.

So all of the other variables are getting me email with right data, but $getunion is empty…

When I pass manually the ID here

$getunion = $wpdb->get_results("SELECT value from wp_bp_xprofile_data where user_id = $get_id AND field_id = 4", "ARRAY_N");

it works… So how can I get the ID?