Comparing sizes of the chicks in these photographs is very difficult, as the camera lens is a very wide angle one and that can cause chicks which are further away from the lens to look significantly smaller then those that are nearer. Here you can see Scrap out of the nest cup and nearer the lens than the chicks inside it. Even so, it looks much the same size as the other two chicks in the picture, which means that in fact it is much smaller than they are!
Today I'm going to try to show some pictures of Scrap, the smallest chick of the brood.