Rep. Gabrielle Giffords is still undergoing physical and speech therapy in Houston, but on Sunday she'll return to Arizona to participate in events marking the one year anniversary of the shooting that left her wounded and six people dead. Giffords' husband, Mark Kelly, plans to speak during a vigil at the University of Arizona. Giffords won't do any interviews while in Tucson and isn't expected to speak at the events, but the fact that she's able to attend already says a lot.