To sync only certain branches from your main family tree:
Open your tree in Family Tree Builder.
Go to Sync (publishing) > Sync Settings. Click ’Advanced Settings‘.
In People to Upload, choose ‘Specific people selected below’ and click on the Select People button.
To add a person, highlight them and click Select. You will probably want to use the eldest ancestors in the tree to get a complete branch.
Now you will see the option to ‘Select People to Upload’:
You should see the name of the person you just added in the list. Clicking the Edit button will allow you to include Ancestors, Descendants and Spouses, any combination of those three or the only the specific person.
You can add more people by clicking Add.
When you finish adding people for a particular branch, click OK to go back to the Sync Settings screen:
Click Sync Now. This will sync a certain branch of your main family tree. This will not affect your main tree in Family Tree Builder.
Important note: If you change the sync settings to include more people or a different branch it will override any previous synced branches. This option does not create a separate tree.
If at any time you may wish to sync the whole tree again, make sure to change the sync settings back to sync all people in the tree.