This doesn't begin to take in the variations time inflicts. A virgin girl has a different gait after she has a child, and it has nothing to do with bubble butts or other appendages. It has to do with the ligaments at the front of the pelvis. During pregnancy, hormones dissolve any bone that may have formed and loosens the ligaments holding the front of the pelvic girdle closed (and those stabilizing it at the spine). The sides of the pelvis spread apart to allow room for the baby to grow, and to have enough space at the opening in the floor of the pelvis for a full term infant to pass through. After the birth, it tightens back up........but never like it was. And subsequent pregnancies just add more separation. The sides of the pelvis rotate outward, and as the hip joint is part of them, the legs move apart. The angle of the hip changes, creating the pregnant waddle (in combination with the extra mass sticking out, of course).
Children have their own unique patterns. Masswise, thing of twin poles close together. Structurally and density wise, they are the same almost right up to puberty.
And none of that includes cultural baggage about what is 'appropriate' for the genders. What clothing is in style also affects things.
If gamesas -does- have a mocap studio, then it would be well worth it to have multiple capture actors. When you use the same animation files over and over, you get to recognize them very quickly. And get bored with them.