I have a small notebook in our book shelves, that my wife and parents know about. It has instructions and log-in details to my desktop computer and our NAS, and

I have a small notebook in our book shelves, that my wife and parents know about. It has instructions and log-in details to my desktop computer and our NAS, and written details for all the most important things they might need straight away. Then my computer + the NAS both have offline KeePass DBs on them with every single password, bank account, etc in them for longer term stuff. The same NAS has all our family photos, scanned documents and contracts, etc. We (wife, kids, etc) all work off the NAS for all our family document storage so they’re familiar with that aspect already.