You definitely need a lawyer to assist you with this matter. You can sue the deputy but you will not likely prevail. He enjoys qualified immunity while performing his duties. You can sue for custody of your daughter. If you already have an order in place then you need to hire an attorney to assist you with bringing an enforcement action; and also determining the proper venue (county) for this case.
The information provided is not advice but a legal perspective and you should schedule a consultation with the lawyer of your choice.
There's no point suing the deputy. You can sue the grandparents. You should definitely get an attorney. St. Mary's Law School has a clinic that offers free legal help. Call the law school or the Center for Social Justice for more information. It's on 36th Street, just off Culebra.
DISCLAIMER: This answer is for informational purposes only under the AVVO system, its terms and conditions. This answer does not establish an attorney client relationship. I am admitted only in Texas. I am not intending this to be legal advice, because I don't know the particulars of your situation. Call me if you would like to discuss this or other issues, 210.501.0880.
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