You do not really provide a timeline here or facts that that are easily understandable. It is not understood what you mean by a disposition date, if her case was ever started, and if it was started, if it was dismissed.
There are many reasons a legal malpractice case may survive despite the "disposition date" of 6/23/11. Without writing several paragraphs on this very complicated issue i suggest you consult a legal malpractice lawyer( blue link below) immediately as time is certainly working against you. If the attorney client relationship continued, if your mom had no reason to know of the legal malpractice or if there was fraud are only a few situations where the case may still survive.
I agree with Mr. Fisher, there are many reasons a case may survive beyond 2 years. Incompetence and the discovery rule (statute runs from the date of the discovery of the malpractice) come to mind. You need to contact a malpractice attorney to present the facts and make a determination.
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