Answer: tweedledum

AnswerCrossword Clue
TWEEDLEDUMOwner of a nice new rattle.
TWEEDLEDUMC. L. Dodgson character.
TWEEDLEDUMOne of an identical pair.
TWEEDLEDUMOne of a well-known pair.
TWEEDLEDUMAlice's entertainer
TWEEDLEDUMIndistinguishable one
TWEEDLEDUMLooking-glass land denizen
TWEEDLEDUM"Through the Looking-Glass" character