rdf(iri("https://example.org/alice"), iri("https://example.org/ancestor"), iri("https://example.org/bob"), iri("https://example.org/family")).
rdf(iri("https://example.org/bob"), iri("https://example.org/ancestor"), iri("https://example.org/carol"), iri("https://example.org/family")).
rdf(iri("https://example.org/alice"), iri("https://example.org/ancestor"), iri("https://example.org/carol"), iri("https://example.org/family")).