When I was born, my brother Lincoln was not quite 2, so I'm sure he felt I was a bit of an intruder....can't help that. We weren't particularly friendly as young children and he and my oldest brother got a lot of mileage out of taunting me and watching me come unglued....which my mother always assured me was done because the loved me :( Time passed, we all grew up in spite of it and by the time we were teenagers, Linc and I were good friends. I dated his friends, he dated mine....wreckless and rebellious, we became partners in crime.
He went off and started his life, I went off and started mine. Jobs, marriages, kids came hurling at us and we stayed in touch less frequently. We checked in. He was always there if I needed him. Generous, kind, but always brutally honest. We spent a lot of time together when Mom and Dad were dying and got reacquainted. I'm so grateful he was there. In recent years we all made an effort to come together whenever possible.
When he got sick, he let all of us know. We all sort of kept track remotely of doctors and procedures and test results. I know he didn't like to share it and got tired of repeating it and just wanted to live his life and so he did. He went back to the things he liked to do, took the trips he wanted to take and it lulled us into thinking everything was okay. And then suddenly, he was very sick....and gone. And it is irreversible.
Death was the first thing that occurred to me when this challenge was proposed. I know it is because it is still so fresh in my memory. But the irreversibility of death is what makes life so poignant and each moment and interaction so important. Hold your loved ones close, do the things you want to do, use the good china. Don't have regrets....those are irreversible as well.