Which one is right?:
I donīt know what the problem with her brother is.
I donīt know whatīs the problem with her brother.
Is it the kind of mistake that even Americans make?
I see!!! But what is the explanation for this? Has it got to do with identifying what the subject is?
I see and hear it:
I don't know what the problem is with her brother.
But since speech often makes use of changed word order to change the nuance or the feelings expressed, often the question form is maintained.