Like many in the world, Julian Lennon, the oldest son of John, is pushing for tougher gun laws in the wake of last Friday's killing of 20 children and six women at an elementary school in Connecticut. He has has been posting messages on Twitter and Facebook regarding gun control, saying, "Action can affect change." He also posted a link to Sign On Dot Org, which is pushing for stricter gun control. Julian knows a thing or two about gun violence, as his father was shot and killed on December 8th, 1980 in New York.