Bukhari Collection: ::Book Number 4:: Hadith # 64
Narrated Anas bin Malik:Um Ar-Rubai'bint Al-Bara', the mother of Hartha bin Suraqa came to the Prophet and said, "O Allah's Prophet! Will you tell me about Hartha?" Hartha has been killed (i.e. martyred) on the day of Badr with an arrow thrown by an unidentified person. She added, "If he is in Paradise, I will be patient; otherwise, I will weep bitterly for him." He said, "O mother of Hartha! There are Gardens in Paradise and your son got the Firdausal-ala (i.e. the best place in Paradise).