Another possibility is that there is a great deal of fear in the household and because the kidneys are especially sensitive to fear, the child may have been raised in an environment that was conducive to kidney pathology such as a brain tumor. It is interesting to note the emotional dynamics in the picture at the top of this page. We see a great deal of concern on the part of the father and the two uncles. That doesn't seem strange at all, considering the circumstances. However, we also see that the child shares that concern.
Some children are especially sensitive to the emotional environment in which they live.
I think that this is the case with this little boy. During the 20 or so minutes in which they were all talking, he did not fidget, he was not looking for something to play with nor was he intrigued by the two foreigners in the room with him, but reflected exactly the emotional state of his father and uncles. Some doctors are like that. However, certainly, this young man gave me something to think about.