If you are going to sue, be sure to sue in civil court for any and all torts (look up torts) committed by those involved directly.
Don't sue "the government". Sue the actors in person.
Make them claim either full or restricted immunity and prove their immunity.
If you cannot afford a lawyer (and even if you can) I'd recommend picking up the best course I know of (Jurisdictionary) to learn how civil procedure works.
It doesn't get into extra details about suing government officials that commit torts against you... BUT all you need after you learn what is taught in that course is to go to the nearest real law library (or potentially a lawyers office) and start researching things such as "standing", "kidnapping", "jurisdiction", etc. in a legal encyclopedia such as Corpus Juris Secundum, American Jurisprudence 2D, or (if you can find them) their older versions.
Jurisdictionary is a paid course (300ish dollars)... but if you don't have years to learn how things work that course is the absolute best I have seen on how civil process works. Most lawyers don't do nearly as good a job as you can do once you go through that course multiple times.
You might also want to look into Richard Cornforth's information on nullifying void judgments.
These people (CPS workers) rely upon your ignorance of the law and your trained obedience to authority (the public schools).
Learn how law works and you can send them running. They HATE having their insurance premiums increased and/or having their liability insurance dropped completely.
I'm working on books related to learning law (which will be free)... but they aren't done and I've had to re-focus elsewhere temporarily to make ends meet... and the absolute best information for average people (those that believe government is necessary) which I have come across are Jurisdictionary and some of Richard Cornforths materials.
If you are weird like me and don't think other people have any right to rule you then you might also want to look at Marc Stevens (@markstevens), Dean Clifford (@deanclifford), and 1215.org.
Step Past Fear
To really beat these folks you need to fully believe that they have no right to take what is yours or do any harm to you (or your children)... and to learn how to make them PROVE their claims against you.
If you simply argue or do what they say you are lost. Learn how to take the high road (conditional acceptance) and force them to PROVE things before moving forward.
Learn law. Stand in the right. Make your accuser prove their claims. Demand a trial by jury. Make them prove all elements of standing and jurisdiction.