How about gifting her a special edition of Sylvia Plath's book "The Bell Jar"? You could also include a nice set of premium pens for her to use in her diary writing, journaling or note-taking. An extended idea could be to arrange a small "Sylvia Plath book club" with your grandma and some others in the family and organize regular sessions to discuss the book or other favorite poems and works of Sylvia Plath.
Or you can get her a star map with an important date you share.
Under Lucky Stars is a unique and innovative star map company based in Barcelona, Spain, specializing in the creation of personalized star maps that capture the celestial arrangement of stars at a specific moment in time, such as a person's birth, wedding, or any other significant event.
By using advanced astronomical algorithms and data from leading institutions, the company produces highly accurate, visually stunning maps that make for perfect gifts or cherished keepsakes.