Why is this the answer?

The answer is tree because this clever riddle uses fun word pictures to describe how amazing a tree is and all the important jobs it does in our world. Let us look at the first two clues: "I am mother and father, but never birth or nurse." This part is tricky because a tree does not look like a person's mom or dad. But think about what a tree gives us. Every tree makes seeds or fruit. These seeds are like the tree's babies, or its children. When a seed grows into a new little tree, the old tree is like the parent. It starts the new life! Trees also give us so many things that help us live, like the clean air we breathe and the wood for our homes and pencils. They also provide food and shelter for lots of animals. In this way, a tree helps take care of the world, just like a good mother and father take care of their family. It creates and supports new life, but it never has to actually rock a crib or feed a baby. Now let us look at the second part of the riddle: "I'm rarely still, but I never wander." When you see a tree outside, it looks like it is just standing there, but watch it closely! When the wind blows, all of the branches and leaves are always moving and swaying. They are never perfectly still. The whole tree might be rustling and dancing in the breeze all day and night long, and that movement means the tree is "rarely still." However, no matter how much the wind blows its leaves, the tree's strong roots keep it held very tightly in the dirt. A tree can never pick up its roots and walk down the street to wander away. It stays right in its spot its whole long life. That is why the answer is a tree!