Although this raises some ethical questions, and illustrates why the safest thing to do with divorcing clients is send both of them to a new preparer.  Do you have written permission from the ex-wife, to disclose to the ex-husband what is on her return?  Do you have her permission to provide her name and SSN to IRS when not addressing an issue involving her return?  And how do you know she hasn't found someone else to amend her return, removing the nominee income, since you saw her last?