Sayyiduna Jabir (may Allah be pleased with him) narrates: When Sayyiduna Abu Bakr (may Allah be pleased with him) and the Prophet (peace and blessings be upon him) set out to emigrate, the two of them went into the cave. In the cave there was a hole, and Sayyiduna Abu Bakr (may Allah be pleased with him) kept his heel over its opening until morning, fearing that something might come out of it and (harm) the Prophet (peace and blessings be upon him). The two of them stayed in the cave for three days, then they left and halted at the tents of Umm Ma'bad. Umm Ma'bad sent word to him: "I see handsome faces, and the people of the tribe are better able to host you than I am." When they spent the evening with Umm Ma'bad, she sent a knife and a goat with a young son of hers. The Prophet (peace and blessings be upon him) said: "Send the knife back and bring me a bowl!" Umm Ma'bad sent word that this goat has neither milk nor any young. The Prophet (peace and blessings be upon him) said: "Bring me a bowl!" So she brought a bowl. The Prophet (peace and blessings be upon him) passed his hand over the goat's back, and it spread its legs and began to give milk. The Prophet (peace and blessings be upon him) milked it and filled the bowl. The Prophet (peace and blessings be upon him) drank himself, gave Sayyiduna Abu Bakr (may Allah be pleased with him) to drink, and also sent the milk to Umm Ma'bad.
Al-Bazzar recorded it; its chain contains a narrator whom I do not know.