The Sun Bonnets (Bunny, Bubbles & Beulah) are a trio of little girl bear singers in the Disney theme park attraction, Country Bear Jamboree.
From 1972's Country Bear Jamboree record album:
The Sun Bonnets (Bunny, Bubbles, and Beulah) are the babies of the Country Bear Jamboree. They began singing in Public School 821 in Clint, Texas, in Miss Grizzly’s class. From there they appeared five weeks running on Major Bear’s Amateur Hour and were booked into Walt Disney World. Backstage they study their lessons (all the cast helps them with their homework, but they get good grades, anyway). In their spare time they are all knitting a scarf for Big Albert, which they hope to have finished for Christmas—three years from now!