Sharing vault with another, existing 1Password user
I have a family account that I share with my wife and two kids. I convinced my sister to buy her own account, and she has a personal account. My sister and I need to share a vault that contains information about our aging parents. I can invite my system as a guest by email, but your invitation appears to try to set up a new account for sister. She doesn't want a new or different account; she wants to keep her account and all her vaults, but we want to be able to share a between brother and sister.
How do I do this?
That is correct, they would become a guest member of the family and would have an account there in addition to their own. So in essence the would have two accounts, their own and the guest under your family. Each will have a different Secret Key but they could share the same password to allow for ease of use.