Musannaf Ibn Abi Shayba 37:217

Ibn ‘Ulayyah narrated to us, from Ayyub, from Nafi’, from Ibn ‘Umar, who said: When the pledge of allegiance was given to ‘Ali, he came to me and said: "You are a man beloved to the people of Syria, and I have appointed you over them, so set out to them." He said: I mentioned the kinship and I mentioned the affinity, and I said: "As for what follows, by Allah, I will not pledge allegiance to you." He said: So he left me and went out. When some time had passed after that, Ibn ‘Umar came to his mother, Umm Kulthum, greeted her, and headed toward Makkah. Then ‘Ali was approached and it was said to him: "Ibn ‘Umar has headed toward Syria." So he mobilized the people. He said: A man would hasten until he would throw his cloak over the neck of his camel. He said: And I came to Umm Kulthum and informed her. So she sent to her father: "What are you doing? The man came to me, greeted me, and headed toward Makkah." So the people turned back.