Only your mom's birth certificate has your grandmo's info. - 回複：

來源: 於 2007-08-04 17:01:26 [博客] [舊帖] [給我悄悄話] 本文已被閱讀：次

so 2 certificates will build such relationship.

I don't think it's necessary to prove the relationship. A hospital document usually will do it.