Smart Copy screwed up most of a family group

Smart copy is a tool and it can only update the information that is selected to be updated.
Care should always be taken to ensure that the correct profile is selected.

If you can repeat the process and demonstrate the issue, please list the steps. It can sometimes be deceiving which profile is the current focus in the new HTML tree. I suggest actually going into profile view and then selecting the URL to make sure you're focused on the correct person. You can also hover over the name and see if it is the same person. The comparison and any listed relationships will give good indicators if you're copying to the right individual.