My husband and I each have 2 chase logins - 1 biz,1 personal. My daughter has one, too.
Each more that 1 Amex login- for some reason I originally couldn't get more than 3 cc's per login.
Each a citi.
Each a credit monitor and then cancel and then again.....
3 diff BB accounts
IME- no problem. Each family member can legitimately use the same computer to manage their own banking/cc's.