Birth is an entry into, and Death is an exit from a particular biological system. Birth is a dip in and Death is a come out.
Animals are always happy and serene, You can never see a 'sad' animal. Every member of the animal kingdom knows that death is an inevitable phenomenon. Every animal-being automatically understands not to expect anything from other beings. Every animal-being perfectly understands that everything happens according to nature's laws.
There are three deaths. First one is the physical death. Second one is where the body becomes a corpse. In the astral death & the final death is where the soul- less astral shell is called 'SCOOP'. is causal death, from there we are promoted to supracausal worlds. However, that happens only when one becomes Enlightened.
Death means the death of a particular experience in a particular physical system. The Energy-Knowledge-Consciousness Entity which got itself integrated with a physical system, thus far, gets separated and goes on its own grand onward journey into various other frequency universes.
Our foremost duty should be the study our own self, and discovering answers to the following questions: 1. Who are we? 2. Where do we come from? 3. What exactly is Birth? 4. What exactly is Death? 5. What exactly is Life? 6. What exactly is the source of human misery? 7. Is misery self-inflicted, or decreed by God, over which we don't have any authority.
Every birth arrival is a cause for celebration and every death departure should be a cause for celebration except for suicide.