Sayyiduna Imran bin Husayn (may Allah be pleased with him) said to Mutarrif: O Mutarrif! By Allah, if I wished, I could narrate hadith I heard from the Messenger of Allah (peace and blessings be upon him) for two days in succession. But what makes me slow to narrate some of it, or reluctant about it, is that some men from among the Companions of the Prophet (peace and blessings be upon him), who were present just as I was present and who heard just as I heard, narrate to us hadiths that are not as they say, even though I know that they do not fall short in (seeking) the truth, or he said: the good. So I fear that it may seem to me as it seemed to them. And sometimes he would say: If I were to say that I heard such-and-such from the Messenger of Allah (peace and blessings be upon him), I would consider that I had spoken the truth. And sometimes he would stand and say: The Messenger of Allah (peace and blessings be upon him) said such-and-such.
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 15331
It is narrated from Sayyiduna Imran bin Husayn (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said to a man: "Did you fast in the last days of this month, meaning Sha'ban?" He said: "No." He (peace and blessings be upon him) said: "Then when you have completed (the fasts of) Ramadan and broken your fast, fast one or two days."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 15332