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Gertrude Hallow ( Gertrude The Great) also known as Gertrude the Great Deceiver) was the first Head girl at Cackle's
Enid's attempt to help Mildred win her first head girl challenge backfires when she summons Cackle's first-ever head girl, Gertrude the Great, to lend a helping hand.
She is an ancestor of Ethel.