If the facts are more robust that you have here, a lawsuit against DCFS in federal court alleging that the case workers violated your constitutional rights as protected by the 4th, 5th and 14th Amendments of the Constitution may be filed.
You need a lot more, though.
See a constitutional law attorney there in Urbana
It sounds like you've had a very difficult time. You should contact a personal injury attorney that also handles family law. There are a few in Champaign/Urbana. They should be able to look at your case for you.
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