For your grandson's birthday gift, I recommend getting him a "mystery movie night" package. You can put together a basket with his favourite mystery movie (or a mystery movie that you think he might enjoy), some popcorn, candy and maybe some soda or his favorite drink. You could also throw in a mystery-themed board game, like Clue or Escape the Room, to play after the movie. Another option is to get him a subscription to a mystery book club, where he'll receive a new mystery book each month. This way he will be able to explore the genre further, and maybe even find his new favorite author!
Or you can get him a star map with the date when he was born.
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.