Verner observes that Neferefre and Nyuserre were brothers, both sons of Neferirkare Kakai, and that Neferefre, Neferirkare's eldest son, was in his early twenties at the death of his father, thus in an optimum position to inherit the throne.
That Neferefre and Nyuserre were brothers, and that Neferefre was in his early twenties at the death of his father in an optimum position to inherit the throne. This was thus. This is what Verner observes. Neferefre is Neferirkare's eldest son. Both sons of Neferirkare Kakai are brothers.