Question: Who is the mother, and what is her date of birth, of Charles the Younger, son of Charlemagne?
SPARQL (Wikidata): SELECT ?value1 ?value2 WHERE { wd:Q3044 p:P40 ?s . ?s ps:P40 wd:Q283107 . ?s pq:P25 ?value1 . ?s pq:P569 ?value2 }