Harmala reported,

While he was with Abdullah bin Umar, Hajjaj bin Ayman came in and did not complete his bowing or prostration properly, so Ibn Umar told him, "Repeat it."When he turned away, Ibn Umar asked me, "Who is this?"I replied, "He is Hajjaj bin Ayman bin Umm Ayman."Ibn Umar said, "If the Messenger of Allah ﷺ had seen him, he would have loved him." Then he spoke of his love for him and the children Umm Ayman had borne.

Azami 10096

Sahih

عن حرملة مولى أسامة بن زيد

أنه بينما هو مع عبد الله بن عمر إذ دخل الحجاج بن أيمن فلم يتم ركوعه ولا سجوده، فقال: أعد، فلما ولى قال لي ابن عمر: من هذا؟ قلت: الحجاج بن أيمن بن أم أيمن، فقال ابن عمر: لو رأى هذا رسول الله ﷺ لأحبه، فذكر حبه، وما ولدته أم أيمن.

الأعظمي 10096صحيح
Contents
Reference
Commentary
Ayat
Collection
Jami al-Kamil
Book
Virtues of the Companions and reports about them
Chapter
Virtues of individual Companions and their reports
Section
Usama was among the most beloved of people to the Prophet ﷺ
Numbering
Jami al-Kamil 10096 (2nd edition)
Azami 10096