With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Down syndrome occurs in about one per 1000 babies born each year.
text_B: Expedition of Abi Hadrad al-Aslami , took place in January 629 AD , 7AH , Shawwal -LRB- 10th month -RRB- of the Islamic Calendar .. Abi Hadrad al-Aslami. Abi Hadrad al-Aslami. In this expedition , the chief of the Banu Jusham tribe Rifa'a ibn Qays was successfully assassinated .
not_related.