In a database you try to avoid storing data multiple times, so if you want to create a database for an adress-book, and your family can login it's very likely you'll get multiple records with the same data if you create a table for each member that can logon.

My suggestion is to create a table with the users (user_id, name, password) and to create a table with the adresses (adress_id, name, adress etc).
To connect the tables you use another table where you store user_id / adress_id information. In that way you only store the data once, and all your familymembers will be able to access their own adress-book.

Good luck