When Disney produced The Muppets in 2011, it introduced a brand new character, Walter. Given Walter’s wide acceptance into the already established Muppet family — by both fans and Muppets alike, it only makes sense that the opportunity is seized in the sequel to introduce another new Muppet to the world (at least one, anyway).
The news comes to us by way of production notes for Muppets Most Wanted provided to us by Walt Disney Studios, who mentions her by name (or at all) just once and in a very manner-of-fact manner. Referring to sets that had to be built that would take all Muppet sizes into consideration, production designer Eve Stewart notes that Muppet sizes range from the seven-foot tall Sweetums to the two-foot tall Carmen. So there you have it, Carmen is two feet tall.