What potential issue could arise when trying to execute PHP scripts within frames?

When trying to execute PHP scripts within frames, a potential issue that could arise is that the PHP script may not be able to access the necessary variables or functions from the parent frame. To solve this issue, you can use the `$_GET` or `$_POST` superglobals to pass data between frames.

// Parent frame
<iframe src="child_frame.php?data=value"></iframe>

// Child frame (child_frame.php)
<?php
$data = $_GET['data'];
echo $data;
?>