What would be the reason for not being able to locate birth certificates for two members of a family? From the 1851 census I know that there are 9 children born from 1828 to 1850. All are listed as being born in Kettle, Fife. There is a birth certificate for Thomas (b1828) but nothing for Jessie (b1830) or Helen (b1832), however all the children after that are recorded. I've located Jessie's death certificate and it records her parents as listed in the census. Any advice would be appreciated.