How about a photo book? I've just done a photo book for my parents for their 70th birthdays.
You could dig up all her old pics and include new ones of your family! I did mine on momento - it should be arriving tomorrow I'm so excited!
It will prob take a lot of work, but its a great way to conserve old pics, and I'm sure she would treasure the book! Something she could look at all the time
Ok, well, I'm going to suggest something really practical. You can get these personal alarm things that the person wears like a necklace (sorry not sure what they are called exactly) and if they get into any trouble they just push a button and it rings a programmed phone number or two. It's great for the elderly in case they have a fall and can't get up or something like that.
I saw a book, like a fancy notebook, in my local gift store that is called "My life" and on each page it has a question, like "What was it like growing up", What do I remember about my parents" "My best memories" etc and they have them for all types of parent and grandparents and great grandparents. Maybe from your kids? I saw it a few days after I came out of hospital having Jazz and wished I had one from my grandad who had just passed. Imagine what she could put in it after 100 years...
When my great Aunty turned 100, her kids made a scrapbooking album of her life for her. It was gorgeous. Took a bit of work, especially organising all the photos, but well worth it.
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