This phrase is said to have originated in KS, and is used as a synonym for female and male genitalia respectively. The story goes that a young
child became frightened when discovering her genitals. She screamed at her mother that there was a "coconut" in there, and she wanted it out, now! Her mother laughed and explained that she, too, had a "coconut" as did the
child's grandma, and, in fact, all the other girls in the whole world. The
child then said that her
father did not have a coconut, he had a twizzler. The common phrasing of coconuts and twizzlers can now be found everywhere.