Who's Missy?

For both GranCCY and Grandad this is the name generally reserved for a granddaughter.  GranCCY's granddaughter has a nickname, Lexi.  She lives and goes to grade school in Lamar, Colorado.  Grandad calls his only granddaughter Missy.  Her given name is Sheryl, and she lives in a state northeast of Colorado near grandchildren of her own.