Twitch CustomAPI - Follower Check

<?php
// Convert Get data to lowercase.
$BroadcasterLower = strtolower($_GET["Broadcaster"]);
$ToLower = strtolower($_GET["To"]);
// Get and decode Follower data.
$FollowerCheckData = json_decode(@file_get_contents("https://api.twitch.tv/kraken/users/$ToLower/follows/channels/$BroadcasterLower"), true);
// Get and decode the correct capitalization of the user in question.
$FollowerCheckName = json_decode(@file_get_contents("https://api.twitch.tv/kraken/channels/$ToLower"), true);
// Get the date and time to be worked with.
$CreatedDateTime = date('Y-m-d H:i:s', strtotime($FollowerCheckData['created_at']));
// No name was entered to see follower relationship with.
if (empty($_GET["To"]))
{
        echo 'You to need to specify a user to see if they\'re following!';
        die();
}
// No such Twitch user exists, yet.
if($FollowerCheckName['display_name'] == null)
{
    echo 'Sorry, ' . htmlspecialchars($_GET["To"]) . ' isn\'t a valid Twitch Account!';
    die();
}
// User isn't following.
if($FollowerCheckData['created_at'] == null)
{
    echo 'Sorry, ' . $FollowerCheckName["display_name"] . ' isn\'t following ' . htmlspecialchars($_GET["Broadcaster"]) . '... Bastard';
    die();
}
// User is following :D!
else
{
    echo 'Yeah! ' . $FollowerCheckName["display_name"] . ' has been following ' . htmlspecialchars($_GET["Broadcaster"]) . ' for ';
    echo GetDateDifference($CreatedDateTime);
    echo ' <3';
}
// Function to get the date difference, grabbed from SO, modified for this use.
function GetDateDifference($datetime)
{
    $now = new DateTime;
    $ago = new DateTime($datetime);
    $diff = $now->diff($ago);

    $diff->w = floor($diff->d / 7);
    $diff->d -= $diff->w * 7;

    $string = array
    (
        'y' => 'year',
        'm' => 'month',
        'w' => 'week',
        'd' => 'day',
        'h' => 'hour',
        'i' => 'minute',
        's' => 'second',
    );
    foreach ($string as $k => &$v) {
        if ($diff->$k) {
            $v = $diff->$k . ' ' . $v . ($diff->$k > 1 ? 's' : '');
        }
        else
        {
            unset($string[$k]);
        }
    }
    return $string ? implode(', ', $string) . '' : '';
}
?>

Example: FollowerCheck.php?Broadcaster=TwitchBroadcaster&To=TwitchUser