Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) narrates: When the Prophet (peace and blessings be upon him) returned from Uhud, the women of the Ansar began weeping over their martyrs. When the Prophet (peace and blessings be upon him) learned of this, he said: "But Hamzah has no women to weep for him." So the Ansar went back and said to their women: "You are not to weep over anyone until you have first wept over Sayyiduna Hamzah (may Allah be pleased with him)." The narrator says: From that time until today this custom has continued: whenever those women weep over a deceased person, they begin with Sayyiduna Hamzah (may Allah be pleased with him).
Al-Tabarani recorded it; its chain contains Yahya bin Muti' al-Shaybani, whom I do not know, and the rest of its narrators are thiqat (trustworthy).