Suggestion:
Hand every server 25 cards (both Kids & Adults) at the beginning of each shift. Each server is asked to have them filled out by the end of their shift and returned to management. Once received the cards are forwarded to someone who is designated as the BCA (Birthday Card Administrator). The BCA separates each card by month, then by date and files them away with the others you have on file. Every month, that month’s cards are mailed 5 days prior to the individuals actual birthday, so that the guest actually receives the card on their birthday (or very close to it). This system is proven to work and builds sales. You can track the returned cards for dollars spent and time frame from birthday until actually redeemed as well as location, etc. This is a fantastic database and does return sales (though once first implemented your return probably won’t be noticed for at least six months ... until the cards actually start being received and returned).