You can do this. The easiest way is to export your existing Family Echo tree and have your family member import it as a new tree on their own account. Use the “Download / export this family ”option and choose FamilyScript, then they can go to “My Account” and select “Create or import new family” and import the file. This will give them their own separate copy that they can edit without changing your original tree. Just keep in mind that photos may not be copied over, so those may need to be added again separately. I’d also recommend keeping a backup of the original tree before making the copy.