@janinenickel Hi Janine.  I’ve never used Squarespace, but from the looks of these forum discussions / posts, comment spam is a huge issue that has not been resolved on their network.

• http://developers.squarespace.com/features-system/post/1044584
• http://vermorel.com/journal/2011/6/29/squarespace-and-blog-spam-filtering-epic-fail.html

It looks like you might be able to use Disqus for comments though (http://help.squarespace.com/customer/portal/articles/91777-using-disqus-for-comments).  I’m not sure that they have built in spam filtering, but usually registration-based commenting systems will cut down on spam because spammers don’t want to take the time to register.

This seems to be a popular related posts third party app for Squarespace that pulls in a thumbnail.

http://help.squarespace.com/customer/portal/articles/73512-how-do-i-add-linkwithin-to-my-blog-entries-

Hopefully there are some Squarespacers in the forum that can help out some more, but I feel like a lot of us are WordPress users.  :)