The term 'Singing Brother's Surname' can be solved by three different crossword solutions: Gibb (4 letters), AMES (4 letters), and Isley (5 letters). The Gibb solution refers to the surname of the English pop group the Bee Gees, which was composed of brothers Barry, Robin, and Maurice Gibb. The AMES solution is the surname of the American folk music duo the AMES Brothers, which was composed of brothers Joe, Gene, Vic, and Eddy AMES. The Isley solution is the surname of the American R&B/soul group the Isley Brothers, which was composed of brothers Ronald, Rudolph, O'Kelly, and Vernon Isley.