Move Parent Post to New Site

Is it possible to change where a parent post resides on a multisite network?

We recently launched a redesign of the main site on our network. We did this by creating a new network site, populating it with the design/content, and changing ‘BLOG_ID_CURRENT_SITE’ in the wp-config.php file to point the new site. Therefore, our new main site has an ID of 121, rather than 1.

So, in our case, we want the parent post to come from the new version (121) instead of the old site (1).

Right now, we have kept the old site around as an archive, and have been updating the parent/child content from there. Ideally, we’d like to do this from the new version of the main site if possible.