Bob and Shan have been married for 26 years and Bob has been responsible for paying all the bills and handling the preparation of their tax return himself. He did not hire a CPA to review his work. Shan has always allowed Bob to sign for her trusting that the return was prepared accurately. Bob and Shan are filing for divorce in the current year and Shan has hired you to help her with the tax return. What exposure does Shan have for previous tax return filings and tax liability?