How do you prevent credit cards from being issued to someone who can't handle them?

I have been named legal guardian over a mentally-ill sibling who has gotten into trouble in the past with spending on credit cards above and beyond her means to pay. I have closed all current accounts, but what is the best way to ensure that no more credit cards are issued to her?

A law to allow "not so smart people" to have credit.
I LOVE IT.
Could you run for president?

On the serious side. There is something called a FREEZE you can put on all three of your reports. I think there is a very tiny charge (a couple of bucks / agency).
Your sister WILL not be able to open ANY new accounts. She will have to do it over the phone so be there with her.
Go to annualcreditreport.com for reports and/or phone numbers.
If she needs credit, they have to call a phone number for approval – make it your number. They will make sure its you by asking you a couple of questions. Such as ss and mothers maiden.

There are companies that charge for this FREEZE service, but you can do this yourself.

Oops, I got the thumbs down before I added that second part. Sorry.
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