Hadith 4224
Sayyida Umm Salamah (may Allah be pleased with her) narrates this statement of the Noble Prophet (peace and blessings be upon him): "Only that suckling establishes prohibition (of marriage) which opens the intestines (i.e., which causes growth and nourishment)."
Hadith 4225
Sayyiduna Ibn Zubair (may Allah be pleased with him) narrates: The Prophet Muhammad (peace and blessings be upon him) said: "One sip or two sips do not establish prohibition."