How does my mom get legal guardianship or custody of my girlfriend?

her dad agrees to hand her over to my mom but we don't know how to proceed with doing so. We plan on moving out of state and my mom must have some sort of guardianship to transfer over schools , all kinds of insurance and medical documents. I'm sure that we will have to go to court but what will we need to tell the judge or ask of him or her?

her dad agrees to hand her over to my mom but we don't know how to proceed with doing so. We plan on moving out of state and my mom must have some sort of guardianship to transfer over schools , all kinds of insurance and medical documents. I'm sure that we will have to go to court but what will we need to tell the judge or ask of him or her?

i just want to add, that we live in new york, and moving to montana

There are many factors that can affect this issue. Firstly, it depends on which state you live in and are moving to. Secondly, there is a matter of time constraints in terms of when you will be moving.

Ideally, if all parties are in agreement - including your GF's Mother as well as her Father - then you can draft a document on your own granting temporary custody and have ALL parties signature notarized. This document will state that your Mother is grated temporary custody and is authorized to act as guardian in all matters and decisions. This will have to be signed by all parties; your Mom, her Mom and Dad, and your girlfriend; with ALL parties appearing IN PERSON AT THE SAME TIME in front of the Notary Public while presenting legal identification (drivers license or passport).
This should suffice temporarily while waiting for the actual court ruling - which can take years.

Please speak with an attorney in your state to verify this information and your states laws.

EDIT: Most Judges are not very keen on granting temporary guardianship to an un-related third party if the basis of the parental transfer is "I can't get along with my parents". Most Judges would be much more understanding to this situation if there is a pregnancy involved, or if the guardianship and move were in the best interest of the minor who has had a drug problem or criminal event - and is trying to leave behind an "unsavory" social element (i.e. drug dealer or gang members). Whereas the move would be beneficial in the minor's recovory or exit from a criminal element.

Below are some links to NY and Montana family law