I am sorry that you are going through this. Sadly, many physicians do not wish to get involved in child custody disputes. It is extremely difficult to make a physician testify, and if you do so you may alienate your child from physicians in your area who will then refuse to take him as a patient. If you wish to change his custody and visitation, you have the burden of showing it is in your child's best interest to do so. I suggest you take your child to the doctor every time you notice problems when he comes back from his mother's. Count your child's medications carefully and keep a journal of the amounts of meds and times your child takes them so it is easy to pinpoint when the child is not getting his meds. Evidence is very important here and these are some things you can do to gather evidence: (1) Save all emails between you and the mother, and enable the full headers for those emails. (2) Do not call her. Only communicate with her in writing.
Last of all, only an attorney licensed in your jurisdiction can represent you. They cannot make a case unless you bring them evidence. Follow that attorney's instructions to the letter.
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