If Facebook is made aware that a person has passed away, it’s our policy to memorialize the account. Memorialized accounts are a place for friends and family to gather and share memories after a person has passed away. Memorializing an account also helps keep it secure by preventing anyone from logging into it.
If you’re a legacy contact, learn how to manage a memorialized account. If you’d like to report a deceased person’s account to be memorialized, please contact FaceBook.

I’m a legacy contact. How do I manage a memorialized profile on Facebook?

To manage a memorialized account:

  1. Go to the memorialized profile.
  2. In the bottom right of the cover photo, click Manage.
  3. Use the menu on the left to do things like:
    o Add a pinned post.
    o Respond to new friend requests.
    o Change the profile picture and cover photo.
    As a legacy contact, you can also request to have the memorialized account you’re managing removed. To submit an account removal request, please fill out this form.
    If you have additional questions about being a legacy contact, you can contact FaceBook.

Source: https://www.facebook.com/help/275013292838654?helpref=hc_global_nav