Did she use the same email for all accounts? Not wise at all.
Getting a new router is the easiest one to do. If she still has control of the computer than I would back up whatever important files and wiped the computer clean and reinstall the OS. The phone and getting back accounts is harder for me to advise other than enable 2-factor authentication, use a password manager with the passwords no less than 25 characters long with none dictionary words or to the max that whatever site allows.