Toys|Dancing Shoes by Noel Streatfeild

After losing their mother, Rachel and her adopted sister, Hilary, move in with their aunt, Cora Wintle. Cora runs a dancing school in London, and she thinks Hilary would be perfect for her dance troupe, Wintle’s Little Wonders! The only problem is that Hilary might be as good as Cora’s precious daughter, Dulcie. Still, Cora is determined to make sulky Rachel and sprightly Hilary members of the troupe.

But Rachel doesn’t want to be a Little Wonder! She can’t dance, and she feels silly in the ruffly costume. Nothing seems to be going as planned … until Rachel discovers her talent for acting.