Not necessariliy. You ought to consult with a family law lawyer in your area regarding a guardianship and how to proceed. It sounds like there's a long case history here which you haven't mentioned and those facts would be relevant to an adjudication in a case such as the one you've described.
Unfortunately, if the child is in foster care through CPS, then you have no power at all to give custody or guardianship to anyone. Only CPS can do that. Sorry!
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