Once, in my backyard, I went out to get closer look at some baby killdeer. There were two of them. The parents flew up and circled about 30 feet above the yard calling constantly to their youngsters. They would, on command, both move and freeze. Ultimately they got to a small tree and flattened the bottom of their neck and chin against the trunk, with their beak pointing straight up against the trunk. They stayed there, frozen, attempting to appear, I suppose, as a thicker part of the base of the tree trunk. It was, to me, impressive that they could, at that young age, already understand these commands from their parents, and impressive how they instinctively knew how to camouflage themselves at the base of the tree. It was fun to witness and after a minute or two I left so they could relax.
The first image here is of a Killdeer with youngsters about. There are 4 young ones. See the blurry one at the top of the photo? The picture below that is a second later, when all of them, on command, scurried under their parent and hid. You can still see one of their legs.
I read today that Killdeer come out of their eggs running.