Know-How Exchange : Other

Hi everyone! My name is Kathy and I was wondering how can I celebrate birhdays of our employees? We have 35 employees now. Last year we have only 15 employees and everyone give small amount of money and we used to buy presents. But now there are a lot of us and I do not know how to marked the birhtdays and make everyone feeling special and happy. My general manager does not want to give a money from company`s account and I just can not ask from the employees to give their money because they would have to give almost every month,sometimes twice a month some amount of money.
Please,help me. Thank you in advance!