It's possible you're thinking of one of these:
* Booker Prize: This is a prestigious literary award given annually for the best original novel written in the English language. It is not associated with a specific birthday.
* The birthday of a specific author with the last name "Booker": There are many authors with the last name "Booker," and if you're thinking of a specific one, please provide more information.
To help me understand your question better, could you please clarify:
* What kind of birthday are you referring to? (e.g., a holiday, a literary event, a specific author's birthday)
* Do you have any more information about "Booker Birthday"? (e.g., any context, a specific date, a website or book)
Once I have more context, I can help you find the information you're looking for.