January 30, 2013 4:42 pm The Cast of “Parenthood” on Parenting Host Cat Greenleaf catches up with the cast of “Parenthood” on the set of the hit NBC show. US & World Videos 1:00 Three dead in apparent murder-suicide in Lowell 3:05 100 protesters detained at Northeastern University 2:39 Community mourns police sergeant killed on duty 2:50 Community mourns Billerica police sergeant killed on duty 4:32 Anti-war protester at Northeastern speaks amid arrests: ‘We are peaceful students'