Mo is commenting on the physical resemblance of Billy Jeff to Joe Kennedy.
Billy Jeff’s Mother’s legs had more airtime than a AA Pilot with 30 years experience. Billy Jeff has a clue who his father was but that is all.
FWIW, the "Mimi Beardsley" story has been out for 8 years.
When it broke in 2003, she was better known by her married name of Marion Fahnestock.
My comment on the 2009 story "Paramour of Kennedy Is Writing a Book (JFK's intern)":
Jackie thought it was a "power mower" that Jack was riding every weekend.
Ba-bum-bump. I'll be here all week! Try the veal!