The term 'singing family' refers to four different musical families: The Wrens (5 letters), the Osmonds (7 letters), the Trapps (5 letters), and the Sinatras (8 letters). The Wrens were a British family of singers and musicians who achieved success in the 1950s and 1960s. The Osmonds were an American family of singers, actors, and musicians who achieved success in the 1970s and 1980s. The Trapps were an Austrian family of singers and musicians who achieved fame in the 1930s and 1940s. Finally, the Sinatras were an American family of singers and musicians who achieved success in the 1940s and 1950s.