The Birthday list is a calendar list of all of your Facebook friends' upcoming birthdays. At this point there is not a way to manually add birthdays to the list as it is generated from Facebook.
Some friends may not be on this list because they may have made their birthday private on Facebook.
- Only friends who made their birthday public to third party apps will appear in the birthday list. If your friends made their birthday private on Facebook, or if they have denied access to third party apps in their Facebook privacy settings, then their birthday will not appear in the birthdays list.