I do know this-
Mars ain't the kind of place to raise your kids
In fact it's cold as hell
And there's no one there to raise them
If you did
But seriously, I strongly believe in the Primordial soup, or prebiotic soup theory. Not necessarily the proposed theory of 1929 published by J.B.S Haldane where he argued that UV radiation provided the energy to convert methane, ammonia and water into the first organic compounds in the oceans of the early earth. Perhaps a better understanding of science such as the proposed idea that gases came from deep-sea hydrothermal vents, or perhaps something else that we haven't figured out yet.
It is unclear whether the conditions to create life could be common to the universe or unique to Earth. People want to believe that since mankind's science cannot yet reproduce the spark of life that it is a false theory or extremely rare. But I say we are in the infancy of our understanding, and we know that "the God of the gaps" keeps shrinking. So maybe we will figure it out one day. And for all we know, life has started more than once on Earth but the dominant life already present has "eaten" it up.
I further believe that with so many stars and so much potential out there, life has started somewhere else, probably more than a few times. But is it primitive, plant, microscopic, developed??? I dunno.
If life did exist at all on Mars, we have seen that life on Earth has clung to the most impossible environments, so I would bet that it's still there somewhere under some rock.