Abrefroth had finished Hogwarts a year ahead of Albus, that was the year Airana had an episode and ended up killing her mother. When I met Albus he was expected to not return to school. Instead Aberfroth wanted him to stay home and care for his sister. Albus was the only one who could keep Ariana calm. That’s why for him the stone was the solution. If he found it, he could revive his mother and be free to pursue his intellectual exploits with me. As for me, I was mistaken to believe that I could use it to raise an army of Inferi. We never found the stone in Godrics Hollow despite finding Cadmus Peverell’s decedents. I wanted to leave and follow his trail, I wanted Albus to come along as well so did he, but Aberfroth was having none of it. A duel broke out in the house and one of us fired a curse that caused Ariana’s Obscurous power to blow up. Albus blamed himself for it... Regardless everything else from this point on you can find in history books. His achievements as well as mine, our battle etc..."