By Liam Gilliver & Paige Freshwater Putting a pet to sleep is the hardest part of owning a dog, but sometimes it is your only option. If you’ve grown up with a furry friend, you know how quickly they become an integral part of the family. Even the idea of having to say goodbye to them one day can fill us with an overwhelming sense of grief. But if they’re growing old and suffering in pain, putting them to sleep is the most humane option. Many owners choose to stand in the hall while the injection is administered, unable to watch their beloved pet die in front of them. But, a vet has issued a d…