After installing the Genesis Framework and Breakthrough Pro child theme, we highly recommend regenerating the thumbnails on your site. This will ensure that all image sizes that are defined in the theme are available in your site as you work to configure all the settings described in this theme setup guide.
To do this, we recommend using the Regenerate Thumbnails plugin.
After you’ve installed and activated the Regenerate Thumbnails plugin, go to Tools > Regen. Thumbnails to regenerate the thumbnails on your site.