The British monarch officially has
two birthdays every year.
Why?

Question

Accepted Answer

One is their actual birthday; the other is the 'official' birthday celebrated with a public parade, usually in June for better weather. — King George II started it in the 1740s. British pragmatism at its finest — if the weather won’t cooperate, reschedule the birthday.

The British monarch officially has two birthdays every year. Why?