Sen. Cory Booker (D-N.J.) and U.S. Vice President Joe Biden beckon to Booker’s family after a ceremonial swearing-in with his mother, Carolyn Booker. (Chip Somodevilla/Getty Images)

About 50 of Cory Booker’s family members and friends descended on D.C.  to watch the former Newark mayor and Twitter rock star be sworn in Thursday by Joe Biden as New Jersey’s junior senator. Guests included Booker’s mother, Carolyn, and brothers, Cary and John Taylor, his rep confirms. Our colleague Ed O’Keefe reports that Booker’s close friend Gayle King was also in attendance; she arrived after her co-anchor duties on “CBS This Morning” in New York.