Before Kennedy and his wife, Vicki, got into a dark SUV, he kissed his daughter, Kara, and niece Caroline Kennedy, and embraced his son, Congressman Patrick Kennedy.
The senator left with a wave to onlookers, and TV news helicopters then followed his 75-mile trip south to his Cape Cod home.
Along the way, he could be seen waving to nearby motorists from the front passenger seat.
Doctors say Kennedy has recovered "remarkably quickly" from a brain biopsy. They say he'll recuperate at his Hyannis Port home over the holiday weekend, waiting for further test results that will help determine his treatment plan.