There isn't an easy solution. You either have to find father and have him sign over the car or sue him for a divorce or some other type of proceeding that will unravel their domestic property ownership and award her the car. If you don't know where he is you might be able to get the court to order an alternative means of serving him, like publishing a notice in the newspaper. You will first have to try to find him and these days a couple hundred of dollars will get you a report from a private investigator and should enable you to find this man. (You will probably need a lawyer to help you figure this out. But try finding the father first by using a private investigator.)
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