How long will this arrangement last? Will pay for the child's schooling as an out of area resident? Do you live in the same school district where your sister in law lives?
You do not need a legal guardian for such a temporary situation. You need a parental consent form to allow your sister in law to handle what needs to be handled for the child. Here is a post that explains when you need a legal guardian appointed for a child.
If there is something you sister in law needs to sign on your behalf to enroll your daughter you can give her a power of attorney. If the principal persists in his or her ridiculous position, contact the district superintendent or your local council person.
This communication is not intended as legal advice. A local attorney should always be consulted for legal advice. No client/attorney relationship is intended or created by this communication.
Below is a link to create a power of attorney. This power of attorney will authorize your sister in law to execute any documents necessary to enroll your child in school, including any applicable parental consent forms. You fill out the form and you will put in the power an authorization to execute any document necessary to enroll your daughter in school including parental consent forms. This power of attorney gets signed in front of a notary public.
For the few hours you are dealing with this should be sufficient for all your needs.
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