Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) invited al-Fadl bin Abbas (may Allah be pleased with him) to food on the day of Arafah, and he said: I am fasting. Abdullah (may Allah be pleased with him) said: "Do not fast, for a vessel of milk was presented to the Prophet (peace and blessings be upon him) on the day of Arafah and he (peace and blessings be upon him) drank it. So do not fast, for people are put to trial because of you (the people of the Prophet's household)."
Hadith Referenceالمعجم الكبير للطبراني / باب الفاء / 15784