Nasai

Imam al-Nasa’i rahimahullah’s intent is that the nephew of Banu Hashim is also not eligible for zakat, because he too is included among Banu Hashim. Similarly, some individuals have used this narration as evidence regarding the inheritance of a nephew, although the discussion here is not about inheritance at all. The meaning is only that a nephew has a strong connection with his maternal uncles, therefore he cannot be considered unrelated to them. This statement was made by the Prophet sallallahu alayhi wa sallam at the time when he had called only the Ansar. He was informed that among those who had come was also their nephew. See: (Sahih al-Bukhari, al-Manaqib, Hadith: 3528)

Relationship Between the Chapter and the Hadith
The Chapter of Sahih Bukhari: «بَابُ ابْنُ أُخْتِ الْقَوْمِ وَمَوْلَى الْقَوْمِ مِنْهُمْ:»
Imam Bukhari rahimahullah mentioned the term "mawla" (freed slave) in the chapter heading, but the hadith that Imam Bukhari rahimahullah presented does not mention "mawla" (freed slave) at all. Therefore, apparently, there does not seem to be a connection between the chapter heading and the hadith. Some have said that Imam Bukhari rahimahullah did not find a hadith mentioning "mawla" according to his conditions, and for this reason, Imam Bukhari rahimahullah could not present it as evidence. However, Hafiz Ibn Hajar rahimahullah has stated that this is not correct. Thus, he writes:
«لم يذكر المصنف حديث ”مولي القوم منهم“ مع ذكره فى الترجمة، فزعم بعضهم اٴنه لم يقع له حديث على شرطه فاٴشار اليه، وفيه نظر لانه قد اورده فى الفرئض من حديث انس ولفظه ”مولي القوم من اٴنفسهم“ .» [فتح الباري 411/7]
It is not correct that Imam Bukhari rahimahullah did not mention «مولي القوم منهم», as some have thought that the hadith is not according to Imam Bukhari rahimahullah’s conditions. This is questionable, because Imam Bukhari rahimahullah has mentioned this hadith in "Kitab al-Fara'id" through the narration of Anas radi Allahu anhu with these words: «مولي القوم منهم» "A freed slave is also included among that people."
Furthermore, Hafiz Ibn Hajar rahimahullah says:
«و وقع فى حديث اٴبي هريرة رضى الله عنه عند البذار مضمون الترجمة وزيادة عليها ”مولي القوم منهم“ ”وحليف القوم منهم“ ”وابن اخت القوم منهم“» [فتح الباري 461/7]
"That is, Imam Bukhari rahimahullah may have alluded to that route of the hadith which al-Bazzar has narrated from Sayyiduna Abu Hurayrah radi Allahu anhu, in which the words mawla, harif, and nephew are all mentioned."
Therefore, Imam Bukhari rahimahullah, by alluding to al-Bazzar and Sahih Bukhari, Kitab al-Fara'id (Hadith number: 6766), sufficed with these very words of the hadith.
Allamah Abdul Haqq al-Hashimi rahimahullah says:
«والظاهر : اٴن عدم ذكر البخاري هذا الحديث هنا مبني على اكتفائة بما ذكر هناك .» [لب اللباب 183/3]

Hadith Commentary:
The name of this Ansari child was Nu'man bin Muqarrin.
In the narration of Imam Ahmad, this is explicitly stated.
In the chapter heading, there is mention of "mawla" (freed slave), but Imam Bukhari rahimahullah has not brought any hadith regarding mawla (freed slave).
Some have said that perhaps he did not find any hadith on the topic of mawla according to his conditions.
Hafiz (Ibn Hajar) said that this is not correct, because Imam Bukhari rahimahullah has included this hadith in the Book of Inheritance (Kitab al-Fara'id), that the mawla of a people is also included among them. And it is possible that Imam Bukhari rahimahullah was alluding to another chain of this hadith, which Bazzar has narrated from Abu Hurayrah radi Allahu anhu.
In that narration, mawla, ally (hareef), and nephew (bhanja) are all mentioned.
It is stated in "Tayseer" that the Hanafis have taken evidence from this very hadith that when there are neither agnatic heirs (asaba) nor those entitled to fixed shares (dhawu al-furud), then the nephew will inherit from the maternal uncle.

Hadith Commentary:
1.
Imam Bukhari rahimahullah’s chapter heading consists of two parts:
➊.
The nephew of a people is from among them.
➋.
The first part is established by this.
To establish the second part, he has alluded to another hadith narrated from Anas radi Allahu anhu, whose words are:
“The freed slave of a people is also from among them.”
(Sahih al-Bukhari, al-Fara’id, Hadith: 6761)
2.
The objective of the Imam is not to establish inheritance for the possessors of uterine relationships (dhawu al-arham), but rather to emphasize the importance of lineage—that by this is not meant only the paternal connection, but also the relationship established through the mother or the connection created through wala’ (allegiance due to manumission) is equally worthy of respect, just as the paternal relationship is honorable.
These should not be violated in any way.
And Allah knows best.

Hadith Commentary:
A freed slave of a people is attributed to them, and likewise, their nephew is also counted among them.
The difference between them is that a nephew can inherit from his maternal uncle, provided there are no other heirs with prescribed shares (ashab al-furud) or agnatic heirs (asabat), but a freed slave of a people does not inherit from them. That is, emancipation is a cause of inheritance from one side only, not from both sides, whereas the nephew’s inheritance is due to lineage (nasab), and thus this lineage is a cause of inheritance from both sides.
And Allah knows best.