Joseph P. Kennedy III in 2010. (Elise Amendola/AP)

Get ready for Kennedy 4.0. Joseph P. Kennedy III, the 31-year-old son of former Rep. Joe Kennedy II and grandson of RFK, announced Thursday he is exploring a run for Congress. The Boston Globe reports that he’s leaving his job as a Middlesex County, Mass., prosecutor to launch his possible bid for the seat Barney Frank is leaving. He and his twin brother Matthew (who works for the Commerce Department) were the third-born of Ambassador Joe Kennedy Sr.’s great-grandchildren — but he appears to be the first of that so-called fourth generation to make a move for public office. Pedigree includes Stanford, Harvard Law, Peace Corps. A year ago, when his first-cousin-once-removed Patrick left the House, it marked the first time Congress had been Kennedy-less in decades.

Read earlier: RFK’s first great-grandchild is born, 6/29/11

Patrick Kennedy discusses leaving Congress after 16 years, 3/12/10

Rookie author Katherine Schwarzenegger steps into the spotlight, 9/20/10

Amanda Smith on the life of Washington grande dame Cissy Patterson, 10/30/11

Read also: Post Politics: A Kennedy will run for Congress, 1/5/11