How about getting her a birdwatching book, such as "The Sibley Field Guide to Birds of Eastern North America"? Or perhaps a birdhouse or bird feeder so she can attract more birds to her yard to observe? Another idea would be to book a birdwatching tour or class for her to participate in.
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.