The father's father has no legal duty.
I am a former federal and State prosecutor and have been doing criminal defense work for over 16 years. I was named to the Super Lawyers list as one of the top attorneys in New York for 2012 and 2013. No more than 5 percent of the lawyers in the state are selected by Super Lawyers. Martindale-Hubbell has given me its highest rating - AV Preeminent - in the areas of Criminal Law, Personal Injury, and Litigation. According to Martindale-Hubbell”AV Preeminent is a significant rating accomplishment - a testament to the fact that a lawyer's peers rank him or her at the highest level of professional excellence." Fewer than 8% of attorneys achieve an AV Preeminent rating. I also have the highest ranking – “superb” – on Avvo. The above answer, and any follow up comments or emails is for informational purposes only and not meant as legal advice.
Neither of the fathers has a legal duty to provide support. Since the accident happened on a road, I assume this was an accident involving a vehicle. Since the injury is so serious, make sure that you contact a lawyer immediately! DO NOT WAIT. Make sure that your lawyer finds out if there was a defective condition with the road, sign, traffic light or something else. In NY, you have 90 days from the accident date to file a Notice of Claim against a government entity.
My answer is for general information purposes (a little more than entertainment) and I do not give legal advice without a personal consultation in New York. I am only licensed to practice law in the State of New York and my answer here pertains to a general question in NY.
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