So are you a young earth creationist, thinking the world is only 6000 years old? Because the fossil record shows death before sin.
That’s not the only option.
Firstly, I would think that death may be built into nature as an aspect of change. Living forms have their moment in the sun in each successive generation. Life sacrifices itself to life, that life will thrive. Observing the relationship that exists between molds and bacteria in their shared environment, we find features in each that control their own growth and that of the other. We can understand creation as a garden, which is eternal and in a state of change.
Secondly, we know that there was a fall before that of mankind. Lucifer and his angels rebelled and were cast to earth. There was a serpent in the Garden of Eden. If we think of angels as God’s messengers, they are the means by which the universe does what it does. The demonic expresses itself not only spiritually, but also psychologically and physically. We spoke of viruses earlier, and can reasonably speculate that they arose originally from what was meant to aid diversity - horizontal gene transfer. That power or authority of nature turned from the good it was meant to confer to bacteria, to its own self interest, causing illness if not death in the process. In tending to God’s garden, we are meant to heal it.
Quantum physics and relativity already describe how weirdly time behaves compared to what we would expect from our day to day lives. I’m going to suggest things that may be even stranger to people’s thinking. Let’s start with the idea that creation occurs from eternity. Ontologically speaking everything is one, all time and space come together as everything is brought into existence by God who is in everything, includes everything and is outside everything. This very now, right here, the word that you are reading, is the connection between a finite creation, a person made in the image of God, and the Now that is in every moment that exists, from the beginning of the universe to its end, the Now that is all moments, and transcends them as It causes them all to be - a Divine Act of Love. God has created a garden universe, which we are destined to tend. Original sin is a primary ontological event that arises within us as we are brought into being and which, we being the crown of creation, has corrupted the universe from its begining to its end. The Garden scene and the crucifixion can be understood as one event. As we reached for the fruit, we drove the spike into the hand of Jesus and into our own. That choice at our foundation is at the core of every moment, where we are broken within and among ourselves and healed in Christ. Time as a journey towards salvation began historically with the first man, and at the same time transformed everything that happened before and would occur after that moment. Causation in other words is not temporal, but from eternity. Everything in time is like a trajectory, except for we who, having a spritual soul can act as causal agents, participating in creation.
Sorry, for now I can’t put more meat on these bones.