Last week, I got to have a colonoscopy. Not had to. Got to.

I am not going to describe the procedure itself in any great detail. First, because even I get tired of discussing That End of Things, no matter the name of this damned blog. And second, because the ins and outs of it don’t matter much, except for that part where I got clocked by narcotics and woke up in a hospital gown feeling like an escapee from the Summer of Love.

What matters: I got to have a colonoscopy.  It was a privilege. I turned 50 last year, and that was a privilege, too. Hitting that mark, and having that procedure, were two milestones my sister missed by 19 years.

I’ve written about Lucy before, and I will again. I can’t not write about her. She was one of the most brilliant, beautiful and caring people I’ve ever known, a diminutive spark plug of a woman with enormous violet-blue eyes and a giant frizz of black hair that bounced and boinged theatrically whenever she played the piano. And could she play. Her Chopin was peerless. Her Brahms was a thrumming romantic force. Her Bach, exquisite and clear. I have a few old cassette tapes of her at the piano, but among the things I miss most — even now, 22 years after she committed suicide — is hearing her crank away the afternoon at the Mason & Hamlin in our parents’ living room.

She’s with me, though. I believe that. Even if I didn’t believe it in a spiritual sense, I would still feel her presence beside me — because I knew, right from the beginning, that I needed to live for the both of us. For all of my childhood and most of my life, my older sister hit every milestone ahead of me; she graduated high school and college ahead of me, had a serious boyfriend ahead of me, had her heart broken ahead of me, turned 30 ahead of me. I expected to trail her forever.

But then her life stopped at 31, and I found myself, at 28, venturing forward alone. But I wasn’t, really. Because every blast of sun and rain I’ve weathered in life, every joy and pain, has been weathered for Lucy, too.

She died without a gray hair on her head, so I’ve gone silver for the both of us. She died without getting pregnant and giving birth and raising children, so I raised my three for the both of us. She died without knowing how it felt to stare down fresh wrinkles in the mirror, so I’ve stared mine down for the both of us. She died without feeling the creep of osteoarthritis in her lower back, so I’ve wolfed back Tylenol for the both of us.

I got to bury our parents. I got to turn 40. I got to feel great love and the loss that followed. I got to watch my kids grow up and up and up, and away and away and away. Last month, I got to pay tuition to two private universities, moving the money around online, watching it whoosh silently from my account to theirs. Last week, I got to fight back tears as I hugged my younger daughter on her move-in day. Tomorrow I get to fight back tears and hug again when I send my older daughter to her semester abroad.

I get to cry. I get to feel. I get to laugh with my friends. I get to eat too much, sleep too little, crab about my knees and wonder about the future. I get to love again. I get to live some more.

And so, as I prepped for my colonoscopy last week, I kept checking myself every time I felt the urge to gripe about the awful food and dreadful laxatives and horrid sea of Gatorade on which I drifted like some sad and bloated whale, high on electrolytes. Lucy didn’t get that far; if she had, she would have made it there three years before me. Instead, I made it for the both of us.

I got to.