Musnad Ahmad 1156:20

Abu Mu'awiyah narrated to us, Hisham ibn Urwah narrated to us, from his father, from Zaynab bint Abi Salamah, from Umm Salamah, who said: The Messenger of Allah (peace and blessings of Allah be upon him) entered upon her, and there was a mukhannath (effeminate man) with her, and her brother Abdullah ibn Abi Umayyah was with her. The mukhannath was saying to Abdullah: "O Abdullah ibn Abi Umayyah, if Allah grants you victory over Ta'if tomorrow, then you must take the daughter of Ghaylan, for she approaches with four [folds] and departs with eight." She said: The Messenger of Allah (peace and blessings of Allah be upon him) heard him, so he said to Umm Salamah: "Let this one not enter upon you."