Sunan An-Nasa'i

It was narrated that 'Aishah said:""Sahlah came to the Messenger of Allah and said: 'O Messenger of Allah, Salim enters upon us and he understands what men understand, and knows what men know.' He said: 'Breast-feed him, and you will become unlawful to him thereby.' (Ibn Abi Mulaikah, one of the narrators said:) For a year I did not narrate this, then I met Al-Qasim and he said: 'Narrate it and do not worry about it