It is narrated from Sayyidah Umm al-Fadl (may Allah be pleased with her) that a woman was divorced by her husband, then he married another woman, and his wife claimed that she had breastfed her. The Messenger of Allah (peace and blessings be upon him) said: "Breastfeeding once or twice does not establish the prohibition (of marriage)."
Hadith Referenceالمعجم الكبير للطبراني / مسند النساء / 21490