But something I've wondered is just how much the wizarding world would have in common with the Muggle world in terms of ideals in child-rearing: if they would be ahead of the times, or if they would be behind the times.Originally Posted by Equinox Chick
I do remember the scene in OotP where Filch was going for the cane and being so excited about being able to use it. I think this implies there might have been a time when Hogwarts staff might have used a cane on disobedient students, and Filch was around at the time, though I'm not exactly sure how long Filch was at Hogwarts for.
I can see Walburga as being a strict sort of mother, but probably seeing Sirius as 'the naughty child'. But parents can look past a lot of their children's faults, and I don't think she would see her son as completely beyond redemption while he was still a young child. She probably just saw him as being strong-willed, and maybe even laughed off a lot of his behavior. Even when he was Sorted into Gryffindor, she might have been disappointed in the results, but I doubt she would have given up on her son at this point. She might having even tried to explain it away.
"It wasn't Sirius' fault. That blasted hat is ancient! It probably just mistook his strong personality for being a Gryffindor. It doesn't mean he still can't do the family proud. But we know this now, and we'll just have to make sure Regulus makes sure to tell that hat that he is a Slytherin!"
But certainly over time, I can see his mother as slowly giving up hope.
As far as the will goes, another possiblity could be that everyone they promised their fortune to died. And I doubt that the Ministry recognizes the Black family's disownment, and probably just decided to promise the money to their next-of-kin.