The Esperanto translation the newspaper provides is fairly literal: "Ho! Vi kaprido!" "Kapro" is the Esperanto noun for "goat," and the "-id" suffix means "child." So it is translating "kid" as "a baby goat." Is there a better translation? I guess it depends on whether "kid" implied a baby goat or a human child back in 1909. If it meant a human child (which I'm guessing), then a better translation might be "injo," which is the affectionate form of "ido," "ino," or (putting them together) "idino."