Consider the following example:
Two students, a native and a non-native English speaker, are given the same, English spelling test.
After they are graded, it turns out that the native speaker misspelled four words, while the non-native speaker had only a single error.
They both return home to their parents and the first one receives congratulations, while the other is being scolded for not having spent enough time to learn the language properly.
Objectively, the performance of the foreigner was better than that of the native student, yet one could argue that speaking English from birth implies knowing the language perfectly; stating that the latter doesn't know their language is entirely out of the question.
The above example might be considered unrealistic and does not necessarily reflect every possible scenario (e.g. where the non-native speaker is good at spelling, but fails at other aspects of the language), but I think it conveys the idea that those born into a particular group would always be considered superior in terms of skills related to that group's culture, environment or other values.
A more realistic, anecdotal example from my own life (also pertaining to language):
During my high school times, there once was a situation where I was talking to my friend (we were both Polish) as we moved toward another room in the school. Then I noticed a printed message on the room's door that asked students not to bring soda inside (in Polish).
I pointed out a spelling error in the text, but my friend was fairly sure there was no error. We started discussing it and then he brought up the argument that he was the one to attend the advanced Polish classes, not me.
At this point I got angry, but I couldn't do much to prove my words. Fortunately, a common friend of ours came; we introduced her to the argument and she confirmed that I was right.
They both attended the same course, so I believe that is what eventually made my interlocutor take back his claim.
It was obvious to me that our choice of extracurricular courses did not reflect our actual language skills at all. He chose the course for particular reasons; my motivations were different, but that did not mean I was not suited for participating in that course.
The two stories might seem unrelated at first, as the first example is, in essence, a story about being allowed (including allowing oneself) to make mistakes, while the other one is more about making a mistake, being unable to notice it, and backing it up with a nonsensical argument. However, I believe that both examples touch on the same issue, the belief that being part of a specific group naturally implies proficiency in everything related to that group.
How could this problem be generalized, and what specific fallacy could it be attributed to?