What is the ruling regarding retaliation (Qisas) and inheritance when one of four brothers kills the second, and the third brother kills the fourth?

Primary text

The ruling dictates that retaliation (Qisas) is incumbent upon the third brother. When the third brother killed the fourth, he did not inherit from him, and the first brother inherited solely from the fourth. The fourth brother possessed half the right to Qisas against the first brother, which reverted to the first brother, thus becoming nullified. Consequently, the third brother owes half the blood money (Diyya). The first brother is entitled to retaliate against the third brother because the first brother inherited nothing from the blood of his second brother. If the first brother kills the third, he inherits from the third, along with what he inherits from the second brother. If the first brother pardons the third brother in exchange for Diyya, the full Diyya is due from the third brother to the first, who is owed half in Qisas. If there are heirs to the fourth brother other than the three surviving brothers, the complexity follows the ruling of the previous case.