There are numerous online “trees” that indicate my great-grandmother’s middle name was Ioan. It was not. It was Iona. Most of the trees list it as Ioan–one typographical error was multiplied over and over. One compiler apparently decided Ioan was a typographical error–only to “correct” it to Joan.
Just because most trees have a “fact” does not mean that fact is right. See where they got it if possible.
And if you differ with them…just make certain that you have records that are consistent with what you are stating to be true.