The Jefferson Family is a wealthy family in Greg's neighbourhood. Not much is known about the Jefferson Family, the only known extended family members are Grandpa JeffersonRowley's Cousins and an unnamed uncle of Rowley mentioned in The Long Haul.

Known Members

             Nuclear Family

           Extended Family


Notice: The appearances are counted only if all the members of at least the nuclear family have appeared.


  • Out of the family, only Rowley Jefferson appeared in all the books, however his father also appeared in all books until Hard Luck.
  • In Cabin Fever, Greg says that Rowley is unfamiliar with the church's rules as his family doesn't visit it regularly.