You ask about the step-mom's right to sign medical and school info. Strictly speaking, she has no legal right to do so. Some agencies and institutions allow a step-parent to sign for homework, records, field trips, etc. - but this is only their policy, not a "right" that can be asserted by your wife. This presents practical problems, since it sounds like she may be more in contact than you with your child's doctors and teachers. I have had other clients resolve this problem by having the spouse (your wife) present (1) a copy of the custody order, and (2) a power of attorney from the custodial spouse (you) authorizing the step-parent (your wife) to sign on behalf of the custodian (you).
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