If it is his page, he can. He needs a link in his page headers like this:
<link rel="shortcut icon" type="image/x-icon" href="http://wp.traceyroad.com/wp-content/uploads/2014/07/design8-3_plain-gray-01-150x150.png">
(to your own image, of course)
Thanks, that's changing the favicon - how can I do it without changing the favicon?