Last week, Tatsuki received his Japanese passport. Now he has both his American and Japanese passports. Both passports are good for 5 years. For children, it is ok to have 2 passports. Adults are supposed to choose one country to have citizenship and give up the other one. But recently many countries are allowing dual citizenship, even for adults. The world is becoming a very international place and there are so many people with parents from different countries. I think that when Tatsuki becomes an adult, it will be ok to continue being an American and a Japanese at the same time.
In Japan, Tatsuki's legal name is フビオ竜生. There is no ローマ字 for his name legally. But when Japanese people get a passport, they have some options about the spelling of their name on the passport. For example, people named 大野 can spell their name Ono, Oono or Ohno. So, luckily, Tatsuki could have his family name spelled "Fulvio" and not "Fubio". The spelling of his name is the same on his American and Japanese passports.
We don't have any international travel plans right now, but all of Tatsuki's family in America is waiting to meet him, so we will probably go there next year.