'Read-only user' mode: Is there one?

I have to look after an elderly relative's stuff, and have set-up a separate Vault in my account with just their items within it (Logins, Bank Accounts, Secure Notes, Identities, et al.). 

Q: Is there a way of giving the relative Read-only access to a Vault on my account holding their information, so they can't go in there and screw-around editing things themselves? 

The reason for this, is that it would give said relative the confidence to use this Vault access with the full understanding they cannot by accident screw-up anything within it while using it in non-edit read-only mode. If that makes sense.

Of course, a side benefit of this would also help me in managing it, as I'd know they couldn't screw anything up as well. A win-win for both parties. 

(NB: How long are we allowed to re-edit posts on these new forums; 10mins...20mins...more?)