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To echo MichaelAMG - it is possible to install wordpress on a subdirectory rather than subdomain so you'd be able to host your blog at mysite.com/blog  instead of blog.mysite.com. For SEO reasons, subdirectory is the recommended way to go. On https://moz.com/learn/seo/domain, Moz explain that search engines view subdomains differently than they do subfolders, which means that it can be harder for successful content in a subdomain to benefit the site as a whole. Companies who host their blogs on subdomains have started moving them to subdirectories and have quite quickly seen positive results, for instance Salesforce moved their blog from a subdomain to a subdirectory and their traffic doubled pretty immediately. If you are installing wordpress instances on one domain it might be a good idea to keep an eye on your permalinks because if you have url rewriting turned on then the different installs can sometimes confuse each other. Just something to watch out for.