There is an old adage in genealogical research that "three sources are proof." Not so. Remember that three "sources" of the same information may actually come from the same source--think about who likely provided information for the death certificate, the obituary, and the tombstone. They probably were the same person.
Try (where possible) to get information from sources that likely had different informants. While that's not always possible, three sources agreeing is not magic.