OK. Here is it. Its Latin name is Harmonia axyridis, one kind of Coccinellidae commonly seen in North America. Wikipedia says, "It is commonly known as the harlequin ladybird (because it occurs in numerous colour forms). It is also known in North America as the multicolored Asian lady beetle, and (because it invades homes in October in preparation for overwintering) as Halloween lady beetle." Here is the photo of their patterns:
red or orange with black spots (form succinea);
black with four red spots (form spectabilis);
black with two red spots (form conspicua).
The one Mia saw should be the succinea form.