Nebula/Tim
Sibling relationships are complicated. Not two are the same, either.
For instance, Dick is smart and looks out for the rest of us. I've always felt I can go to him for advice and he'd know the answer. Sometimes it's not the answer I want to hear but sometimes it's the one I need to hear.
Jason and I haven't always gotten along. Some days we still don't but recently it has gotten a lot better. Despite our disagreements, I trust Jason to have my back. If ever I got into a fight, he is the one I want to be fighting beside me.
Our youngest brother and our sister aren't here so you wouldn't know them. But still, I have a very different sibling relationship with both of them as well.
Point of the matter is I don't think you can just go "Right, well, that style of relationship works for them. We should do it that way." because honestly, it's not a one size fits all thing. Complicated, I know. But that's family.