The need is to be able to register relatives' information on all employees, so that you can easily get in touch with them in case of e.g. emergencies.
To solve this need, you will have to use the following:
1) Access custom fields via the User module and create the fields of the type "Text" seen in the image below (just for inspiration)
2) Edit user and add content in the newly created fields, and finish with SAVE
3) View the newly created fields on the frontpage of a user's information
Now you are done and can add the rest of the content to all users