Even if there is no specific birth date mentioned in the source, it is recommended to provide a Birth event and estimate the dates based on other (life) events around the person. A concrete example would be the mentioning of a Baptism event, by which the date of birth can be estimated, for instance by setting the `sem:hasLatestEndTimeStamp` property to the date of the Baptism event. Example: ```ttl _:person1 a roar:PersonReconstruction ; rdfs:label "Susanna de Bock" ; pnv:hasName [ a pnv:PersonName ; pnv:baseSurname "Bock" ; pnv:givenName "Susanna" ; pnv:literalName "Susanna de Bock" ; pnv:surnamePrefix "de" ] ; bio:event [ a bio:Baptism ; bio:place _:location1 ; bio:principal _:person1 ; sem:hasActor [ a sem:Role ; sem:roleType [ a sem:RoleType ; rdfs:label "baptized" ] ; rdf:value _:person1 ] ; sem:hasTimeStamp "1697-02-28"^^xsd:date ] ; bio:birth [ a bio:Birth ; bio:principal _:person1 ; sem:hasActor [ a sem:Role ; sem:roleType [ a sem:RoleType ; rdfs:label "born" ] ; rdf:value _:person1 ] ; sem:hasLatestEndTimeStamp "1697-02-28"^^xsd:date ] ; roar:documentedIn _:saaId10160347 . ```