from the 1950s or so, girl who kept saying "eee gad"

Hallie Parker and Annie James are identical twins who were separated at a young age due to their parents' divorce. Unbeknownst to their parents, the girls are sent to the same summer camp, where they meet, discover the truth about their relationship, and come up with a plan to switch places in an effort to reunite their mother and father.

Two identical twin sisters, separated at birth by their parents' divorce, are reunited years later at a summer camp, where they scheme to bring their parents back together. The girls, one of whom has been living with their mother and the other with their father, switch places after camp and go to work on their plan, the first objective being to scare off a gold-digger pursuing their father.