回複：禮拜一就要把父母移民的申請寄走了，請皮爺和八爺最後給把一下關

You may add the copy of your birth certificate into your parents' applications, respectively though you have included the 母子關係公正/父子關係公正. Also, your parents need to provide their birth certificate, respectively for their I-485.

By the way, You do not need to pay the I-864 filing fee ($70) for both of your parents because this fee only needs to be paid to National Visa Center only if your parents apply for their immigration visa in China using consular processing. Filing I-485 within U.S. does not need to pay this fee.