Question: which was the  deathdate   of thomas  boyiston adams who's father is  abigail  adams?
SPARQL (Wikidata): SELECT ?value1 ?value2 WHERE { wd:Q206191 p:P40 ?s . ?s ps:P40 wd:Q7787805 . ?s pq:P570 ?value1 . ?s pq:P22 ?value2 }