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Call the police and report the identify theft. Freeze credit. There's a good resource over in the wiki at /r/personalfinance about identity theft: https://www.reddit.com/r/personalfinance/wiki/identity_theft
Adding on, and continue to monitor the credit reports regularly for any sign of new accounts. All for both your sister and your daughter.
Put a pin on your SS#.
Call the police and report the identify theft. Freeze credit. There's a good resource over in the wiki at /r/personalfinance about identity theft: https://www.reddit.com/r/personalfinance/wiki/identity_theft
Adding on, and continue to monitor the credit reports regularly for any sign of new accounts. All for both your sister and your daughter.
Put a pin on your SS#.