Miss Rachel is a good one
Mine does this, I'm not concerned, he's chilling out and absorbed in it just like I do when watching something mid afternoon or something really good.
But I just try and limit to 1hr max in a day in small chunks like 15-30min and not every day.
What is he watching? Maybe it’s to stimulating for him? Could try a more mellow show like puffin rock on Netflix! X