It sounds like you have a dispute with your eldest child over the custody of their sibling (your child). You will need to take your case to the probate court or whatever court gave guardianship or custody to your eldest child. Contact a family law attorney.
For informational purposes only. Not legal advice.
I apologize if I am incorrect, but I think you are the same person who has been asking this same question over and over again for the past month or so. You apparently are not satisfied with the answers the Avvo attorneys have provided up to now, and I do not see this changing.
For your own sake, please find a knowledgable lawyer take his/her direction.
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