If she committed fraud or theft, then those are bases to have the discharge of her debt denied in a Chapter 7 case. You need to file a complaint objecting to the discharge of the debt in the bankruptcy court case and go through a trial to establish the required elements. You will likely need an attorney for that. There are strict deadlines for bringing the Complaint, and they are stated on the notice of commencement of case you should have received.
The above does not "get you" the $20,000 back, but merely gives you the right to continue trying to collect on it pursuant to the laws of the state where she lives (e.g. filing a lawsuit, getting a judgment, garnishing wages, etc.)
If there are assets being distributed in this Chapter 7 (which is unusual, but could happen), then you should be sure to file a proof of claim for the amount owed to you so you can share in any distribution from the Trustee.
Mark J. Markus, Attorney at Law
Handling exclusively bankruptcy law cases in California since 1991.
http://www.bklaw.com/
bankruptcy blog: http://www.bklaw.com/bankruptcy-blog/
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