Well, one is red/cream (not sure how dark he'll get) and white, one is blue and white, and I can't tell if the other 2 are both black or if one is a tortie. In one pic it kind of looks like she has a bit of red.
Torties are always girls (well, 1 in 3000 is a boy. . .hardly worth mentioning :tongue2 so I think you're right!. And, yeah, I looked at the picture bigger, and the little one all stretched out in your hand is definitely a tortie. Is the other dark one all black?
Miami is a Tortie but looks like something else is going on there.... She may be a Tortie Smoke.
But for any kittens to be a smoke, one of the parents MUST be smoke or silver . It is possible Nouni might be a Blue-Cream Smoke and White . A smoke would have hairs that are white or almost white at the roots.