Very interesting information
Anyone who shtams from Hungary (i.e. their parents or grandparents came from Hungary) is technically considered a Hungarian citizen under Hungarian law. What this means is that they can go to any Hungarian consulate in the world (New York, LA, Tel Aviv), either in person or via mail, and apply for a Hungarian passport. Since Hungary is part of the EU, this means they can then travel (or even move) at any time for any length to Hungary or any of the 26 other EU countries — England, France, Poland, etc. — without obtaining any VISA or any prior notice.