Tina Grimmie, the mother of late singer Christina Grimmie, has died of breast cancer. "We are saddened to announce the loss of our beloved Tina," the Grimmie family said in a statement Sunday. "She will be missed immensely." Christina Grimmie was 22 years old when she was shot and killed while signing autographs during a meet-and-greet following a concert on June 10, 2016. InsideEdition.com's Keleigh Nealon (http://twitter.com/KeleighNealon) has more.