Brown performed a necropsy and concluded that Hailey had been poisoned with ethylene glycol, the main ingredient in most antifreeze brands. The chemical tastes sweet and has an enticing aroma. 2-year-old Elly also started showing symptoms and had to be euthanized a couple of days later. The family installed surveillance cameras around the home and called the Maui Humane Society. Investigators are now looking into three other suspected poisoning cases in the same neighborhood. One ailing dog is being treated by a veterinarian.