Calender help

[rocksolid_101]

I desperately need help with this problem I have been having.
I have synced my calender on my android phone with my gmail account which has been working fine.
However the birthday calender only partially syncs meaning I am able to see some birthdays but if I go on the gmail website and check the calender, but there are some birthdays there but are not showing up on my mobile device. Does anyone have a

What I am using is samsung galaxy nexus

 

[patruns]

I don't follow. What is a "birthday calendar"? I put birthdays in a regular calendar and they show up in notifications just fine.