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If life originated on two planets in our Solar System then it must be a lot easier for life to originate than we thought. Why are we not seeing this in the Universe at large (the Fermi Paradox)?
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The so-called Fermi paradox and similar conjectures are based on erroneous and obsolete suppositions. We now know to a high degree of confidence that ALL forms of life on Earth have a common origin. Plants, animals and the rest in all their wondrous variety (the vast bulk of which are completely invisible to us), are in fact only the evolutionary products of a single instance of life.
We do not know whether our own planet was the source of this single instance of life and given the rapidity of life's occurrence here after the Earth was formed, there is a chance that it wasn't. Discoveries of organic molecules - sometimes called "building blocks" - elsewhere in the solar system and the wider universe, suggest other possibilities. Exchanges of inorganic material within our solar system via meteoritic and possibly cometary impacts, provide a mechanism whereby life or proto-life compounds could be transferred between planets and/or their moons.
Consequently, it is possible that life elsewhere in the solar system and the wider universe, may be widespread, given semi-reasonable conditions for its existence (and endless aeons of time for it to slowly evolve and propagate). Even so, all this may only be the evolutionary products of the same single instance of life.
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Advanced civilizations should have conquered the problems of large distances and be leaving evidence everywhere. There's been plenty of time for communication signals to reach us from billions of light years out.
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The life-forms that we see around us are complex special cases that have adapted to relatively benign environments. The vast bulk of life on Earth is microbial and exists in places and conditions that seem barren and hostile to our own delicate sensibilities. eg. crustal rocks, antarctic ice, the upper atmosphere. If we were to remove just one single species from the c. 5-10 million presently in existence (and the countless numbers of extinct species), then no other advanced life-form would be left on our planet. And no doubt the whole place would keep happily ticking away without us, just as it did before we evolved.
Personally, I fully expect that we will eventually discover life on Mars and elsewhere in the solar system - the conditions are harsh but not unliveable for simple cellular organisms. And when we do discover such life, I expect we'll find that its chemistry matches our own, just as all life on Earth does. Where it actually originated, we may never know.