Oh, dear ... hadn't been aware of Michelle being that much younger than Kirstie.
Well, then again, when Robin Curtis, as Saavik, informed Kirk of David's fate, she still managed to deliver the line very effectively. On one hand, it was spoken as a dispassionate Vulcan and on the other, it was still expressed in such a way that it seemed like she was tapping her mental disciplines to shield herself from the pain and mental anguish, as well. As Ro, though, Michelle Forbes definitely had that edginess that Kirstie Alley had and was definitely of the same caliber, talent-wise. TNG really lucked out in casting Michelle, the way they did. As I recall, she actually first appeared on a throw-away episode centering around Deanna Troi's annoying mother. It was a bit part, but you could tell that this actress was something very special. In fact, TNG marked the start for a lot of great actresses careers, of the day ...