It sounds like he was shooting down at the nest from the second floor. The boy was on the first floor. And none of this makes sense. Almost had to have gone through a window. This is not the type of accident a normal person could have, the shooter has to be a little slow or not right in the head.
You're right.... half of the details I needed were right in the article.
Of course, the other detail... 'what kind of a person does something this stupid?' - that question is still pending ;~\