How do I combine my sister's personal FamilySearch account with the profile in my family tree?
Hope that made sense! I had previously entered a profile for my sister in the tree and it was assigned, obviously, an ID. My very much "Living" sister later signed up for her own FamilySearch account and was assigned a different ID. How do we combine the 2 accounts? I can't find her personal account to merge, assuming because she is alive and her profile is protected. Any suggestions are appreciated!
You can't combine profiles for living people; as you surmise, they're protected, for privacy. Each of you will have different IDs for each other in your accounts, and you'll each need to make your own edits to your profiles. You'll connect to the shared tree with your deceased relatives.2
After someone dies, sometimes a whole slew of duplicate profiles pop out into the public tree space, where they eventually get merged.
Some contributors here populate their private tree space with a lot of information about living relatives. Some contributors do not enter any information about living relatives. What you do is your choice, and is independent of what your sister does.0
Here is a brief document that may answer more quiestions.