Before revision: The dolls were first created in the late 1950s, and introduced in 1959, before becoming one of the United States' biggest toy fads in the early 1960s.
After revision: The dolls were first created in 1956 or earlier and were larger and made from a softer, more rubbery material than the smaller versions that became popular in 1959, before becoming one of the United States' biggest toy fads in the early 1960s.