Simplify the following text for a Grade 9 native English-speaking person.
Original: Parma grew tremendously after World War II when the young families began moving from Cleveland to the suburbs and during the Cold War Parma kept Nike missles in underground silos .
Simplified: Parma 's tremendous growth came after World War II as young families began moving from Cleveland into the Suburbs . During the Cold War , Parma 's Nike Site Park housed Nike missiles located in underground silos .