TIFU by leaving my skin medication on the counter.

So a few months ago my Grandmother came from Ohio to spend a week at my house. We have a bonus room that she could sleep in and I was responsible for cleaning it up to standard, which I did very well. However, in my bathroom was my jar of anti-acne medication. I did not think twice about leaving it in there as it was in a pump jar, and was obviously not toothpaste. Unfortunately, My grandmother failed to notice this, and managed to mistake it for toothpaste and brush her teeth with it. I guess it was the middle of the night, and she did not want to turn the light on, but her use of it was pretty unexplainable. She did not tell us she had done this until she had returned home for a couple of weeks. She complained that she had lost her taste and appetite. The fact she had done this was pretty funny to me and I laughed about it on and off for several weeks, untill she started complaining about being lethargic and gaining weight. Long story short, she had at this point developed late stage colon cancer, and passed away a couple weeks ago. Which is to bad, but it happens. I just feel bad for laughing about it.