What we know:

Deputy Press Secretary Bill Burton will brief the WH press corps traveling with the President at 1:30pm at Oak Bluffs filing center.

President Obama will attend and speak at tomorrow's Celebration of Life memorial service. The First Lady will also attend.

Pool Report from the Boston Globe's Jenna Russell:

Just before noon -- about two dozen motorcycle police from Barnstable, Brockton, and the state lined up outside the Kennedy compound. A half-dozen empty black limousines and several black Cadillac Escalade SUVs rolled into the compound, preparing to pick up family members for the procession to Boston.

Inside the home, family members gathered for a private Mass as the senator lay in repose.

Dozens of media tested microphones and watched closely of any sign of activity. Children in bathing suits and towels around their necks watched from the porches of neighboring houses.

12:38 p.m. -- The Mass is underway inside the residence, a woman in a black dress was visible through the front window, a child in her arms with the child's arms around her neck ... a flag flew at half-mast in the center of the circular driveway surrounded by clusters of fading brown hydrangeas...a handful of neighbors are watching quietly behind a white picket fence...uniformed members of an honor guard gathered at the side of the white-shingled, green-shuttered house, then moved to the front porch.

12:49 p.m. -- Still holding at the Kennedy home.

The Mass is being held in the "fun room." It's overlooking the ocean, and it's the room the family traditionally holds Mass in. Officiating at the Mass is Donald MacMillan from Boston College. The honor guard has nine members representing all branches of service from Washington D.C. They're described as Armed Forces body bearers.

1:47 p.m.

Senator Kennedy left his beloved Cape home for the last time. Two members of the honor guard rolled the casket, draped in an American flag. On the driveway, the full honor guard lifted the casket from its platform, and stepped slowly in formation down the driveway.