My traveling companion (last name is LI) is the child of a chinese immigrant. He was born in the US in 1950 and his mother was American. Both his father and mother are now deceased. In reading visa requirements, there is a section about children of chinese descent. His father did become a US citizen in the 1940s. Do we still need to send his birth certificate and verification of his father (chinese born) citizenship? We're not sure if we have any papers relating to his father's citizenship. We do have death certificates.

Also, he did travel to Macau once several years ago on a day trip while in Hong Kong. Would have have a visa on one of his old passports for this? He was detained by customs when reentering by 2 hours! No problem getting in but out was a hassle. Was never told why.

What should we do?