Pam -
you need to specify, are you talking about a custom script that is running the two sites, or are you using wordpress like all your other posts talk about ???
If it's a custom script, then they should be able to share the same database with a few code changes. If your talking about using wordpress for two domains from the same database, it can be done, but it's a lot more headaches than it's worth. Better to just have siteB feed off of siteA with a plugin like
https://wordpress.org/plugins/feedwordpress/
