I think I figured this out. . . 1. Go to the family member person sheet who already has the desired source attached. 2. Click on the Sources tab of this person. 3. Identify the desired source listed. 4. Click on the blue "View Source" link. 4. After this opens up, click on the blue "View" link near the top that just appeared. 5. After this opens up, click on the blue "+ Copy to My Source Box" link. 6. A pop up window will confirm that you have successfully copied the source to your Source Box. 7. Next, go to the new family member's person sheet and click on the Sources tab. 8. Click the blue "Add Source" link at the top. A pop up menu will appear. Click on the "Attach from Source Box" option. 9. The new source you just added will appear at the top of your Source Box list. 10. Check the box to the left of this source and then click on the blue "Attach" link to the right. The new source will appear in the new family member's Sources list. You may want to edit the title and remove the "Copy of" text that was added to the source title which is an artifact of this process. Enjoy!
I guess that works. If the source is a FamilySearch source (found in system and not from outside like Ancestry) then it is easy to attached to family members. Where it is attached to someone from their source page, click review attachments and then you can move and align family members also in the record. If it is attached to a neice, grandparent or other extended family member I go to the record image and along the bottom where it has the names indexed there is usually a blue box on left of name that will bring up that person in relation to the document. I can select that and go the the page where I can attach it and I use the ID number of the person I created. I myself do not use the source box feature much.