A relationship is a fact like any other and has to be proved like one. Records establish part of it, a birth entry, a marriage certificate, an adoption order, and those records carry gaps, particularly where they were made in a system that recorded less or recorded it differently. Where the documents run out or are doubted, the case is built instead from the ordinary traces of a shared life. This subject sets out what each kind of record establishes and what stands in for it when nothing was ever written down.
DNA testing establishes biological relationship with very high confidence, which resolves some questions completely and others not at all. Legal parentage may exist without a biological link and may be absent despite one. Where testing is used, the collection procedure, the accredited laboratory and the documented chain of custody determine whether the result is accepted.
