Your grandpa will not be issued a U.S. Passport unless he is a citizen. He may be able to come for a visit if he obtains a visitor visa. Based upon the information provided he will likely need an INA 212(d)(3) waiver. He will also need to establish ties outside the U.S. I would encourage you to discuss the matter with an attorney. You can read more about visitor visas at http://myattorneyusa.com/travel-visas.
Answered on Nov 04th, 2016 at 2:29 PM