"And a one and a two..." If you watched TV during the 50s and 60s, you probably heard Lawrence Welk on the accordion and saw his tiny bubbles every week. Once or twice a show he'd announce, "Please welcome the lovely Lennon Sisters." Three or four of the sisters harmonized on his show regularly from 1955 to 1968, singing popular songs of the times and standards like this one from Rodgers and Hammerstein's "The Sound of Music."
The Lennon Sisters started as four of the twelve Lennon children: Dianne, Peggy, Kathy, and Janet. While their music was more popular with parents than teens, they did have "teen star" PR, even including publication of a Nancy Drew style mystery, "The Secret of Holiday Island," (which is on the "kids' shelf" in my parent's library). More recently The Lennon Sisters are back in the limelight in parodies on Saturday Night Live. Some of the original sisters, along with brothers and cousins, still perform at Welk Resorts in California if you want to catch the real thing.
In "The Sound of Music," Julie Andrews leads the Von Trapp family singing and yodelling "The Lonely Goatherd" as part of a marionette show. (This is during a happy family time before they flee the Nazis across the Alps to freedom, eventually ending up in Vermont.)