Translation:The child asks the farmer a question about his cows.
Hm, I was looking for some real evidence but I can't find anything right now.
One doesn't 'vraag' a 'vraag'.
A 'vraag' is a 'question'.
With the verb 'vragen', you are asking a question.
You either ask a question or you have a question.
You don't use 'vragen' for asking a question and then refer to the question as an object of your asking a question. This is an unnecessary duplication.
You either have a question, 'een vraag', or you ask something (= "je vraagt iets").