We are currently working on the option to manually add dates to the calendar on the family site.
As of now, all dates in your calendar are taken directly from your family trees on that site.
While you are working on it, could you please make an option for showing birthdays on the calender without the year of birth. Some of my women ralatives didn't like their ages revealed! Also a relative brought up that it may present a personal security risk because of the current risk of identity theft. The tree is deficient without being able to enter birthdates so it would be great to have the option to also hide it on the tree. My relative uses another program to build his tree and has that option.