Who is Muhammad ibn al-Hanafiyyah, and how did his mother, Khawlah al-Hanafiyyah, conceive him? Is it true that Imam Ali (may Allah honor his countenance) had a wet dream and wiped his penis with a piece of cloth, then Khawlah wiped her vagina with the same piece of cloth and conceived while she was a virgin? What is the timeframe in which that could have happened?

Ibn al-Hanafiyyah is Muhammad ibn Ali ibn Abi Talib, and his mother is Khawlah bint Ja'far. As for what was mentioned in the question regarding the cause of his birth, there is no basis for it in accredited historical texts, and we do not know if it is possible for it to be a cause of pregnancy; specialists can be consulted. A Muslim should wash semen if it gets on his clothes. Slander is a grave crime, and it is impermissible to accuse a Muslim of adultery without clear evidence. The majority of scholars hold that adultery is not proven merely by the appearance of pregnancy.