My condolences for your mother. Try to think of the good things, don't beat yourself too much.
My condolences. I am very saddened to hear of your mother. The thought of losing a parent hits close to home for me right now. I have recently become painfully conscious of my own mother and father's imminent mortality. My dad and my aunt were both menopause babies. They had 5 older brothers who were all grown-ups when they were born. My grandfather was almost 60 when my dad was born. I never met my grandfather or grandmother. My dad's older brothers all died in their mid-60's. My aunt is now in her mid-60's and experiencing all the same health issues that my older uncles experienced. If her health follows the trend established by my older uncles, she won't be around this time next year. Then all that leaves of the family is my dad, heading quickly into the age range that all his siblings died in. He's already having health issues. I've had to make myself think of things that I've always taken for granted. My mother's family has historically had longer life spans than my father's, but my mother is not in very good health. I think she's still got quite a few years, but her health worries me, especially in light of my father.I got a tear in my eye reading about the way that letter and those pictures gladdened your grandma's heart, Stantor, for the description of your grandma, offered by your aunt, precisely describes my own mother, in her younger years.
Three weeks ago, as a light drizzle fell, we laid my mom to rest, and since then, I have spent a fair amount of time comtemplating all the "woulda and shoulda" occasions in the past, when I missed chances to gladden her heart with the sort of simple gesture you describe above.