The brotherhood of islam and the love of the companions among themselves.

 The brotherhood of islam and the love of the companions among themselves. 

Alhamdulillah, The love the sahaba had among themselves is something beyond our mind and they loved one another more than a mother could love her child. 

The messenger of Allah salla Allahu alayhi wasalam built love among the Muhajiruun and the Ansar together and bond them like no other one else. 

As Allah says, 

Aal-e-Imran 3:159

So by mercy from Allāh, [O Muḥammad], you were lenient with them. And if you had been rude [in speech] and harsh in heart, they would have disbanded from about you. So pardon them and ask forgiveness for them and consult them in the matter. And when you have decided, then rely upon Allāh. Indeed, Allāh loves those who rely [upon Him].

Allah says, 

Al-Hujurat 49:10

The believers are but brothers, so make settlement between your brothers. And fear Allāh that you may receive mercy.

As reported in hadith of something the sahaba did beyond our minds

Narrated Sa`id bin Jubair:

Ibn `Abbas said, "In the verse: To every one We have appointed ' (Muwaliya Muwaliya means one's) heirs (4.33).' (And regarding the verse) 'And those with whom your right hands have made a pledge.' Ibn `Abbas said, "When the emigrants came to the Prophet (ﷺ) in Medina, the emigrant would inherit the Ansari while the latter's relatives would not inherit him because of the bond of brotherhood which the Prophet established between them (i.e. the emigrants and the Ansar). When the verse 'And to everyone We have appointed heirs' (4.33) was revealed, it canceled (the bond (the pledge) of brotherhood regarding inheritance)." Then he said, "The verse: To those also to whom your right hands have pledged, remained valid regarding cooperation and mutual advice, while the matter of inheritance was excluded and it became permissible to assign something in one's testament to the person who had the right of inheriting before.

Sahih al-Bukhari 2292.

Even when a companion died, he was to inherit from his companion due to the love placed among them.

Allah says in Quran,

Al-Ahzab 33:6

The Prophet is more worthy of the believers than themselves,[1] and his wives are [in the position of] their mothers. And those of [blood] relationship are more entitled [to inheritance] in the decree of Allāh than the [other] believers and the emigrants, except that you may do to your close associates a kindness [through bequest]. That was in the Book[2] inscribed.

Such was the brotherhood of Islam.