Narrator names are parsed automatically from the isnad; identity and biographical details are matched from rijal sources (Itqan narrator profiles, muslimscholars.info).
The freed slave of Usama bin Zaid said, "Al-Hajjaj bin Aiman bin Um Aiman and Aiman Ibn Um Aiman was Usama's brother from the maternal side, and he was one of the Ansar. He was seen by Ibn 'Umar not performing his bowing and prostrations in a perfect manner. So Ibn 'Umar told him to repeat his prayer.
Harmala, the freed slave of Usama bin Zaid said that while he was in the company of 'Abdullah bin 'Umar, Al-Hajjaj bin Aiman came in and (while praying) he did not perform his bowing and prostrations properly. So Ibn 'Umar told him to repeat his prayer. When he went away, Ibn 'Umar asked me, "Who is he?" I said, "Al-Hajjaj bin Um Aiman." Ibn 'Umar said, "If Allah's Messenger (ﷺ) saw him, he would have loved him." Then Ibn 'Umar mentioned the love of the Prophet (ﷺ) for the children of Um Aiman. Sulaiman said that Um Aiman was one of the nurses of the Prophet.
Narrated Al-Hasan Al-Basri: When Al-Hasan bin `Ali moved with army units against Muawiya, `Amr bin AL-As said to Muawiya, "I see an army that will not retreat unless and until the opposing army retreats." Muawiya said, "(If the Muslims are killed) who will look after their children?" `Amr bin Al-As said: I (will look after them). On that, `Abdullah bin 'Amir and `Abdur-Rahman bin Samura said, "Let us meet Muawaiya and suggest peace." Al-Hasan Al-Basri added: No doubt, I heard that Abu Bakra said, "Once while the Prophet was addressing (the people), Al-Hasan (bin `Ali) came and the Prophet (ﷺ) said, 'This son of mine is a chief, and Allah may make peace between two groups of Muslims through him."