It doesn't seem right to let the day pass without acknowledging her.
For years it was a dilemma when people would ask me how many siblings I have. I have 2 brothers, and technically that would have been the correct answer to the question. To say I had a sister who'd died risked unplanned emotions when people would inevitably ask what had happened to her. It was one of those awkward gray areas like how honest to be if someone asks how you are and things actually aren't going well. Sometimes it's surprising how complicated an answer to a simple question can be.
One of my favorite literary works is Naguib Mahfouz's Cairo Trilogy, which follows the life of an Egyptian family from WWI to the 1950's. I came to care so intimately for this family. In the first book Palace Walk one of the sons was killed in a demonstration--perhaps against British rule? I don't remember. He was referred to by his grief-stricken family as 'my late (brother) (son) Fahmy'. That seemed like a dignified way to refer to a deceased relative, simple, but conveys information clearly and gently. Unfortunately it seems a little quaint in the context of modern American culture and so I never felt comfortable using that either.
This summer will mark the 20th year since her death. She left behind a daughter, now 21. My beautiful niece was 19 months old when her mother died; she never got to know her mother (and her mother never got to see what a wonderful daughter she had) because my sister was in a coma for 19 months before she died.
I called and talked to my mother on this day. An acknowledgment of the truth that having children means having your heart outside of your body and away from your ability to protect--always at risk of being broken.