Bibles. The older ones usually contain a wealth of information. How does someone find the family Bible?

I was searching for information about an ancestor. Information for this ancestor “came up” in my search. However, my ancestor lived in Kentucky, and the record was in Missouri. And, the source for the information was a family Bible. How did my ancestor’s information get written in a Bible in Missouri? He never went there – he was born and died in Kentucky. So, I began researching the ancestor’s children. And, there was a daughter who was in Missouri! One of the children had married and moved to Missouri. And, this child had taken the family Bible with her!