I just skimmed the original article in the "Süddeutsche Zeitung".
According to that he was a very caring father, very close to the kids. They mention that they considered it a family like the others, but that their father was often away.
The boy, Dyrk, says he was very close to his father.
I'll post the URL to German readers. If you read German you can see it there.
longjack