Question: When is the date of death and birth of Louis IX of France's child with Margaret of France, Duchess of Brabant?
SPARQL (Wikidata): SELECT ?value1 ?value2 WHERE { wd:Q346 p:P40 ?s . ?s ps:P40 wd:Q457111 . ?s pq:P570 ?value1 . ?s pq:P569 ?value2 }