It appears just fine! ^^
When you update a pet's items, sometimes the old image is displayed instead. Basically what happens is your computer browser saves information, like images, to your computer and displays them instead of having to grab new information from the site every time you load a page, this allows pages to load faster. But in this case, your computer saved the old image and is displaying that, and doesn't realize there is a new updated image its supposed to be showing instead.
It will update on its own eventually, but you can also fix it by doing a hard refresh (Ctrl+F5) or clearing your browser cache (which is where it saves all that information)