Is it true that the Companion Muhammad ibn Abi Bakr killed the third Caliph, Uthman ibn Affan, may Allah be pleased with him, and what was his role in the Fitna, if any?

Muhammad ibn Abi Bakr was born during the Farewell Pilgrimage, and Ali ibn Abi Talib took charge of his upbringing. He was a devout and diligent worshipper. Aisha grieved over his killing and took on the upbringing of his son, Al-Qasim. The correct account is that he did not kill Uthman nor did he participate in his killing. Rather, when Uthman reminded him of his father’s standing, Muhammad left him remorseful and departing.