Kiu Fung's life after he was exposed as a Khitan and kicked out of the Beggar's Union and became a pariah in the Central Plains was pretty miserable. He subsequently lost his teacher and his adopted parents and, perhaps most tragically, Ah Chu at his own hands.
Amidst all that tragedy, however, I wonder if becoming brothers with Hui Juk and Deun Yu was the one bright spot in Kiu Fung's life after Ah Chu's death. He seemed to genuinely enjoy hanging out with his two younger sworn brothers. When Kiu Fung joined with Deun Yu to celebrate Hui Juk's marriage to Dream Girl in Hsi-Hsia, that seemed to be the happiest Kiu Fung ever was during the entire DGSD story (at least in the 1981 TVB adaptation).