Question: When did John Adams have child Thomas Boylston Adams, and who is the mother?
SPARQL (Wikidata): SELECT ?value1 ?value2 WHERE { wd:Q11806 p:P40 ?s . ?s ps:P40 wd:Q7787805 . ?s pq:P569 ?value1 . ?s pq:P25 ?value2 }