Using Email & Secure Messaging
First and foremost, EMAIL IS NOT SECURE. When using email to communicate about your loved one's business or health information, never send sensitive information by email; neither through attached documents or in the body of the email. Bad actors can and do intercept email to obtain Personal Identifiable Information to hack accounts, impersonate people and a number of other illegal acts.
If you need to communicate sensitive information with others, use secure messaging platforms that offer end-to-end encryption by default such as Apple's iMessage, Signal, WhatsApp and Telegram (through its secret chats feature only) among others.
But, even on these platforms, send only the minimal information that is needed and nothing more. For example, if someone asks you for your loved one's age, provide the age and don't share the date of birth unless they specifically ask for it.
Using Secure Cloud Storage
Cloud storage refers to services that allow individuals and businesses to store data on remote servers, which can then be accessed via the internet. You can store documents on cloud storage, organize them in folders, and if needed, share documents using a link and a password. Examples of cloud storage include Google Drive, Dropbox, Microsoft OneDrive and iCloud.
Cloud storange can be accessed from a cell phone so that you have immediate access to your important documents.