These things are difficult for a human to duplicate. If the whole nest has fallen, a substitute nest can be built and placed close to the original nest site. Fledglings are fully feathered young birds not yet capable of flight. They jump from the nest and frequently end up on the ground. Their parents are usually close by and will find them by sight and sound to continue to feed them.
Rabbits can build their nests in tall grasses or garden mulch piles.
The nest is usually a shallow depression covered with fur and grasses. If you accidentally uncover a nest, gently replace the babies and cover them back with grass or pine straw. Rarely will you see the mother since she stays away from the nest deliberately and only feeds the babies early in the morning or late in the evening. Helpless youngsters frequently fall victim to the free-roaming dog and cat. Keeping dogs on leashes and cats indoors will help curb this infant mortality.