Christine Leinonen, mother to one of the victims of the Pulse Nightclub attack in Orlando, will take the stage Wednesday night at the Democratic National Convention to tout Hillary Clinton’s efforts on gun control and endorse her presidential run. Leinonen’s son, Christopher “Drew” Leinonen, 32, was a gay rights activist and one of the last victims to be identified. His boyfriend, Juan Guerrero, 22, was also killed. Leinonen was one of the first to join the vigil on the scene the morning of the attack, and has said she will cope with the "overwhelming" sadness by honoring his memory, spreading a message of love and acceptance. She will be joined on stage by two survivors of the attack, Brandon Wolf and Jose Arriagada.