The stars and planets are created by divine consciousnesses to serve as a playground for life. The life is seeded on planets and other places and is allowed to evolve. Special higher dimensional consciousnesses watch over the life development, guiding and cherishing it. There is always cross-pollination of life between different worlds. Sometimes it is physical - the life is carried from one place to another. Often it is non-physical - the forms of life are copied from one planet to another non-physically. They could simply appear or seem to be created by chance.
We are aware of some of the supernatural consciousnesses who are responsible for the creation, development and support of life-forms in the universe - these are fairies and elves. There are other consciousnesses involved which are not as well known. Fairies and elves are not dimensional beings, they are the ones that exist outside dimensions and support the function of dimensions. To illustrate: recall human workers who are working in supportive functions - system administrators, cleaning people, security guards, plumbers - they have all the keys, and walk among other employees almost invisibly.
It is not clear to me whether life in the universe developed on all planets in parallel or whether each planet goes through stages. I need to research that.