If there's a "Frieburg" somewhere, I don't know where it is.
Multi-culti is really not unusual these days. It takes less time to fly from Kansas to France than it takes to drive from Kansas to California. I was appalled when Sherrod Brown guessed there were 250,000 to 300,000 American citizens living overseas. There are probably that many just from Ohio. We are NINE MILLION Americans Abroad, with exactly zero representation in DC, and only a scattered few who care (half of them, because I know them and harass them about it!).
It is well known that the U.S. passport is often the most expensive passport in the world to own. There are only two countries in the world that do not recognize Residence-Based Taxation (RBT). They are: Eritrea in Africa and the USA. Those two countries tax their citizens wherever they live. All others do not. The USA does have Double Taxation Treaties with most countries. These are supposed to eliminate any citizen getting taxed at more than the higher of the two countries in case of a residence abroad. The trouble is that these things were written decades ago, and do not take into account more recent things like a Roth IRA, or S-Corp income. Due to this, plus the fact that I have a German residence but US-based income, between Germany and the USA, I am expected to pay about 73% in income taxes. Heil Honecker! You don't know how often my Swiss friends have been telling me I'm insane not to move down there, but my wife has her 98 year old mom to take care of, and all her friends nearby (i.e. Düsseldorf), and I can't ask her to just uproot her life at age 73 for the sole reason of alleviating my financial woes. My daughter in New York gets no problems from the Germans, because her legal New York residence is good enough for the Germans to leave her alone. My other daughter in Germany makes scads of money (several multiples of what I do), but she works for a top international law firm. Her income comes from all over the world, and they know how to structure that so that she never pays more than 50%, even after the USA gets whatever cut they want from her.
In election years, I keep getting requests from candidates in places I never heard of, asking me to "step up" with a contribution. I tell them, "look, to send you a non-deductible $100, I have to earn $400. How am I supposed to keep that up if my tax bracket isn't brought down to 50%?" So, they all say, oh yes, if I'm elected, I will get on that, and introduce a bill for RBT. Well, plenty of them HAVE been elected, and I'm still waiting to hear about a bill introducing RBT. The right will probably say, "but we need the money to patrol the border!" (yeah, and fund your "fact-finding" trips to play golf at Trump's resorts) Then the left can counter, "but there are two American billionayahs living tax-free on yachts harbored off of Monte Carlo!" I'm sure there are. The 9 million others of us don't count, of course.
So, best of luck to your multi-national family. I hope they manage to navigate the land mine of international taxation. The number of us with US income and foreign residence that manage to navigate it free of scars are few and far between!
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