Back in the olden days someone--I forget who it was--made a calendar that noted the birthdays of all the MC regulars. I just have it on my iCal, which notifies me of people's birthdays one day ahead of the actual day. Don't know that you're on it, though.
I don't control that calendar and can't add anyone to it. That's why it would be nice to know who made it!
Kate sent me a hard copy a while back. I'll post the iCloud link here for all to share after I go through and make sure I haven't added anything personal to it by mistake.
What is the url for your shared birthday calendar? That way I can make sure mine has all the same info.