The Parent Trap
Hayley Mills plays twins who, unknown to their divorced parents, meet at a summer camp. Products of single parent households, they switch places (surprise!) so as to meet the parent they never knew, and then contrive to reunite them.
plays Susan Evers / Sharon McKendrick
plays Margaret 'Maggie' McKendr…
plays Mitch Evers
plays Charles McKendrick
[sorry, no trailers found] -- try searching youtube.com