Musnad Ahmad 1153:93

Sufyan narrated to us, Hisham and al-Zuhri narrated to us, from Urwah, from Aisha, who said: Aflah ibn Abi al-Qu'ays came to me seeking permission to enter upon me after the hijab had been imposed. The one whose milk Aisha had been nursed by was his brother. So he came seeking permission to enter upon me, but I refused to grant him permission. Then the Messenger of Allah (peace and blessings of Allah be upon him) entered upon me and said: "Grant him permission, for he is your paternal uncle." I said: "It was the woman who nursed me, not the man." He said: "May your right hand be covered in dust, he is your paternal uncle."