Most birds build nests to live in. the place where a bird lives with its young ones is called a nest. They build their nests in a safe place where enemies cannot reach and also to lay eggs.

Birds build their nests with grass, feathers, twigs, paper, old clothes, rags, wool, mud and leaves. They work very hard to build their nests. They fly again and again to collect the materials for their nests.

As soon as the nest is ready, the mother bird lays the eggs in it. Both the father bird and mother bird sit on the eggs to keep them warm. The father bird also protects the nest and keeps enemies away. When the baby bird is fully grown, the egg shell breaks and the baby bird come out of the egg shell. The baby birds are quite helpless.  They do not have feathers. Their eyes are closed and they are too weak to fly. So the mother and father birds look after them.

Image via Wikipedia

Image via Wikipedia

They feed them, keep them warm, and protect them from enemies and bad weather. The mother bird takes the food in her own mouth, breaks it into small pieces and makes it soft and then passes it into the mouth of the baby bird.

Once the baby birds grow up and have feathers, the parent birds teach them how to fly and find food for themselves.   

With out all this care the baby birds would never grow up. They would die.

Thus, the young ones are cared and protected by their parent birds till they learn to fly and gather their own food.