Maria Shriver is "gutted" by the deaths of longtime friends Rob Reiner and wife Michele Singer Reiner, whom she said "never stopped" being committed parents. "I loved them, and I knew they loved me, for any friend like that is such a gift," Shriver, 70, wrote via an Instagram tribute to the late couple on Monday, December 15. "They gave me and all their friends that gift all the time." She revealed, "They loved their kids so much, and they never stopped trying to be really good parents," amid news that Rob and Michele's son Nick Reiner has been arrested on suspicion of committing the murders.