Behind every statistic there is someone like Jenny or Gretl. Their friends and family say things must change

Gretl Petelczyc (L) with her friend Maddie Hillbeck. Hillbeck says ‘we all need to come together and make the change that Jenny and Gretl would have wanted to see’. Photograph: Madeleine Hillbeck

Police were almost at Jennifer Petelczyc’s home in Perth’s wealthy western suburbs when the final gunshot rang out.

By the time they made it inside the Floreat house, they found Mark Bombara had already shot two people and then taken his own life.