It's a minefield, because circumstances change. I am one of four girls, with a much younger stepbrother. (not my mother's) My mother and stepfather decided many years ago, when all of us four were happily married to wealthy men, to leave half of their money to my stepbrother, and divide the remainder amongst the four of us as we were all provided for. We were all very cross at the time because it was mostly our father's money that was about to be divvied up. Move forward twenty years and all four of us are broke and struggling, stepbrother has become a male model and is wealthy. So we are now really angry because stepbrother is not even in contact with his father and yet could inherit our father's money. We wish they had just divided it equally amongst all five of us.
My husband's family are far fairer, all money is left equally to the next generation on all sides of the family. They then choose if they wish to pass some down through the generations.
I have a friend who I think is behaving appallingly. She is due to inherit her mother's house, because she has ME and isn't married, so her mother is worried about how she will live. Her sister, who is married, will inherit nothing. but my friend knows that her sister would love to leave her husband but can't afford to. And my friend has a partner who she passes off as her lodger so that her family won't be suspicious. Who has just inherited his own mother's house.