Cambridge family grateful for police officer who found missing girls Jennifer Eagan WCVB A mother and father sent a thank you letter to Cambridge police for helping to find their daughter and her friend after they went missing Monday afternoon, according to the Chronicle's news partner, WCVB. Heidi Tridello Mattern, who is 5 years old, did not realize walking away from Raymond Park in Cambridge, out of the view of her babysitter, would send her parents into a panic. "So me and my friend were playing at the park. Then we disappeared," Heidi said. "I thought of the worst things that would happen," the girl's mother, Giada Tridello Mattern said.