My older sisters didn't pressure me to join their sorority at all, but I think it might have been another story if I'd been rushing at the same campus they went to.
I really hope my younger sister goes Greek (she's starting high school this fall, so I've still got four years to work on her), and to be honest, I'd really like her to join DZ especially since there are chapters at all the schools she might end up at. I think I'd actually be sort of hurt if she joined my older sisters' sorority, because they have that to share with each other and I'd really like somebody in my family to share my own affiliation with.