'He does not have any special education needs and there are no discipline issues in the school. He is not disruptive, as a child he is very pleasant,' added Mr McCavera
This suggests to me that the parents are not putting in any effort.
On the rare occasions that I had to discipline my 2, I established very quickly that the removal of their mobile phones and computer access for a period of time always seemed to do the trick.
Perhaps if Mum and Dad were put away for a month and the son had to be placed in a home for the duration, all 3 might get the message.