Hey sarah,
I am really sorry that delay of this reply,
I've checked in your site, the reason why the calendar is not show up is because your site got doing some URL backslash rewrite, for example : If I trying to access
http://www.yoursite.com/blog/ then it will redirect to
http://www.yoursite.com/blog so causing Easyblog ajax URL issue.
To fix this, I already applied some fix in your site ->
JoomlaFolder\administrator\components\com_easyblog\includes\easyblog.php
// LINE 4047
$url = rtrim(JURI::root(), '/') . '/' . $language . '/?option=com_easyblog';
// Replace with
$url = rtrim(JURI::root(), '/') . '/' . $language . '?option=com_easyblog';
it should work fine now, can you give it a try now?