I think it’s a mix. With my twin, we have some similarities (both physical and mental) and some differences.
In some ways, we act the same, but in others, we balance each other out. What she is really good at - I tend to suck at and vice versa. I think we learn from each other, so she’s teaching me to be better in some areas, and I’m trying to do the same for her.
But I don’t think we’re expected to be the exact same in every way.