I would either give her a framed pic of you and her when you were a child, her younger days, something that has meaning. Or I would give her a book about grandaughter's and grandmother's. Or....the neat thing that ppl are doing here now is going to a one night painting class. It is a 3 hour class where the entire class paints the same picture and it is done when you leave. You can give that to her as a gift b/c you painted it yourself. I would also write her a 'love letter' so to speak. Write her exactly how you feel and what she did for you through your childhood and lifetime. Tell her how much she means to you. Give her a good book with a bookmark. Give her a coupon book that you made yourself offering her things like "an entire day spent with me", "lunch with me", "cleaning your house", "day of shopping", etc If she is able, take a class with her...take a painting class, take a cooking class, a cake decorating class, etc I took a sewing class with my grandma. She already knows how to sew but we took a class that taught us how to make a particular item. My grandma also loves to paint so one year I gave her a book on paintings, new brushes, gift card for new paint, etc I also like to take photos of things she likes to paint like barns, lighthouses, etc She then paints them for a hobby and then sometimes she even gives them to me! I frame them, hang them in my house, and take pics of them in my home for her to see. She lives in Fla and can't travel anymore....
happy bday to your grandma, cherish her. My grandma means the world to me.